Non-contact density measuring device for desulfurization absorption tower

Abstract

The utility model discloses a desulfurization absorption tower non -contact density measuring device, including absorption tower, densimeter measuring bucket, differential pressure transmitter and defoaming tank, absorption tower is connected with densimeter measuring bucket through sampling pipeline, differential pressure transmitter has positive pressure side and negative pressure side, positive pressure side and negative pressure side are connected with densimeter measuring bucket through pipeline, densimeter measuring bucket has positive pressure side sampling port and negative pressure side sampling port, and the interval distance h is established between positive pressure side sampling port and negative pressure side sampling port, the defoaming tank is located densimeter measuring bucket top, differential pressure transmitter is connected with DCS system, the utility model not only can accurately measure absorption tower densimeter accurately, realizes periodic sampling measurement, flushing and backwashing function simultaneously, and effectively reduces the economic cost of later spare wear replacement, equipment regular maintenance.

Description

Technical Field

[0001] This utility model relates to the field of desulfurization treatment technology, and in particular to a non-contact density measuring device for desulfurization absorption towers. Background Technology

[0002] Slurry density is a crucial parameter for the operation of desulfurization absorption towers in thermal power plants. Proper slurry density control effectively utilizes limestone powder as a desulfurizing agent, ensures the quality of the gypsum slurry, and significantly reduces the power consumption and wear of circulating pumps, gypsum pumps, and agitators. This, in turn, effectively reduces limestone powder usage, lowers power consumption, and improves desulfurization efficiency. Because the slurry's pH value is generally maintained between 5 and 9, it exhibits strong corrosiveness. Therefore, most measurement technologies focus on non-contact measurement, although some flow meters utilize contact methods. The current research status and patent applications of density meters for desulfurization absorption towers are as follows:

[0003] 1) Dynamic Differential Pressure Density Meter. Working Principle: Based on the liquid pressure calculation formula, ΔP=ρgh, where ΔP is the differential pressure; g is the acceleration due to gravity, a constant of 9.8; and h is the sampling height. That is, at a constant height, the current density is calculated by measuring the differential pressure. Specific Procedure: High-level and low-level sampling ports are installed on the wall of the desulfurization absorption tower. Samples are taken manually to the differential pressure transmitter, and the slurry density is calculated using the transmitter's differential pressure. However, the measurement environment inside the desulfurization absorption tower is extremely harsh. The slurry is affected by factors such as the dynamic pressure of the slurry circulation pump and agitator starting and stopping, the oxidation fan, and air bubbles within the slurry itself, causing frequent fluctuations in the dynamic differential pressure measurement value. The actual online measured density value deviates significantly from the actual manual measured value, reaching a maximum deviation of 80 kg / m³, making it unsuitable for reference by operators.

[0004] 2) Online continuous radiometric density meter. Working principle: Based on the exponential decay law of narrow beams of X-rays or gamma rays, I=I0e -umxm Where I is the radiation intensity after passing through the sample; I0 is the radiation intensity before passing through the sample; u m u is the sample's mass attenuation coefficient for X-rays. m =u / ρ (where u is the linear attenuation coefficient of the sample to X-rays, and ρ is the density of the sample); x m The density of the sample is determined by the following procedure: A radioactive source stably emits X-rays or gamma rays of a certain intensity during decay. These rays pass through the sample inside the container and are absorbed and attenuated by the sample. The higher the density of the sample, the greater the attenuation, thus allowing the sample density to be calculated. While this method allows the radiometric densitometer to adapt to the measurement environment of desulfurization absorption tower slurry, the measurement system requires a separate radioactive source generation system and detection system, resulting in very high costs. Furthermore, the presence of radioactivity poses significant safety risks to equipment maintenance.

[0005] 3) Ultrasonic Densitometer. Working principle: Based on the relationship between the speed of sound and the velocity of liquid when ultrasound propagates in a liquid. Where C is the propagation speed of ultrasound in the liquid; ρ is the density of the liquid being measured; and K is the compressibility coefficient, which is a constant for a specific liquid. That is, the transmitter generates an ultrasonic signal, which passes through the liquid being measured and is received by the receiver. The propagation speed is calculated by combining the transmission and reception times, and then the density of the liquid being measured is calculated. In this method, the ultrasonic flowmeter is suitable for measuring slurry in absorption towers. However, because the transmitting and receiving devices are in direct contact with the slurry for extended periods, slurry adheres to the walls. Furthermore, continuous operation over long periods causes a decrease in the accuracy of the measuring elements, requiring periodic calibration of the equipment, resulting in high maintenance costs.

[0006] 4) Mass density meter. Working principle: Based on the Coriolis principle, it measures the relationship between the vibration frequency of the vibrating body and the density of the liquid being measured. Let f be the vibration frequency with or without the test liquid flowing through the vibrating tube; k be a constant determined by the vibration mode; E be the elastic modulus of the vibrating body; I be the stiffness coefficient of the vibrating body; ρ be the fluid density; A be the transverse cross-sectional area of ​​the vibrating tube; and L be the length of the vibrating tube. That is, when the material, geometry, and shape of the vibrating tube are constant, the vibration frequency is determined only by the mass of the vibrating system. The mass of a given volume of fluid flowing through the vibrating tube is determined by its density. When the density of the test liquid changes, the natural frequency of the vibrating tube also changes. Based on the proportional relationship between vibration frequency and the square root of density, the density of the test liquid can be calculated. In this method, the mass flow meter is a contact measurement, and the vibrating body is in direct contact with the desulfurization absorption tower slurry sampling system. Due to the continuous flow of the slurry, internal impurities easily cause wear on the vibration measuring element, leading to reduced measurement reliability over long-term operation and high maintenance costs for replacement parts.

[0007] Static pressure gauge density measurement. Working principle: Based on the liquid pressure calculation formula P2-P1=ρgh, where P1 and P2 are the first and second pressure gauges respectively, g is the acceleration due to gravity (constant 9.8), and h is the sampling height. That is, when the liquid to be measured flows sequentially through the first and second differential pressure gauges, the pressure difference can be calculated by comparison, and then the density of the liquid to be measured can be calculated. In this method, static pressure gauge density measurement belongs to a contact-type densitometer, and its core is the densitometer measuring device. This method has two problems: First, the measuring cylinder itself cannot eliminate air bubbles in the slurry, and the slurry settles rapidly during the measurement process, making it impossible to guarantee measurement accuracy; second, the pressure gauge is in direct contact with the medium being measured, and long-term operation can cause slurry sedimentation inside the sampling tube, leading to blockage. Furthermore, the slurry being measured is corrosive, posing a risk of internal corrosion, reducing the accuracy and reliability of the measurement. It also cannot achieve remote transmission or online measurement under program control. Utility Model Content

[0008] The main purpose of this invention is to provide a non-contact density measurement device for desulfurization absorption towers, aiming to solve existing technical problems.

[0009] To achieve the above objectives, this utility model provides a non-contact density measuring device for desulfurization absorption towers, including an absorption tower, a density meter measuring tank, a differential pressure transmitter, and a defoaming box.

[0010] The absorption tower is connected to the densitometer measuring tank via a sampling pipeline. The differential pressure transmitter has a positive pressure side and a negative pressure side, which are connected to the densitometer measuring tank via pipelines. The densitometer measuring tank has a positive pressure side sampling port and a negative pressure side sampling port, with a distance h between the positive pressure side sampling port and the negative pressure side sampling port. The defoaming box is located on top of the densitometer measuring tank. The differential pressure transmitter is connected to the DCS system.

[0011] Furthermore, the sampling pipeline is equipped with a manual sampling door and a motorized sampling door.

[0012] Furthermore, it also includes a flushing main pipeline for flushing the slurry within the pipeline after measurement.

[0013] Furthermore, the main flushing pipeline includes a flushing branch pipeline connected to the sampling pipeline and an overflow pipe connected to the defoaming box. The flushing pipeline is sequentially equipped with a manual flushing water valve, an electric flushing water valve, and a manual backwashing sampling valve.

[0014] Furthermore, it also includes a discharge pipe connected to the density meter measuring barrel, and the discharge pipe is equipped with a discharge electric valve.

[0015] Furthermore, diaphragms are provided at both the positive pressure side sampling port and the negative pressure side sampling port.

[0016] Furthermore, the sampling pipeline is provided with a dredging component near the outlet of the absorption tower. The dredging component includes a rotating rod, one end of which is hinged to the inner wall of the sampling pipeline, and the other end is fixedly connected to a dredging rod. A guide plate is provided at the connection end between the rotating rod and the dredging rod.

[0017] Furthermore, multiple rotating rods are arranged in a circumferential pattern within the sampling pipeline.

[0018] Furthermore, in its initial state, the rotating rod is attached to the inner wall of the sampling pipeline, and during pipeline flushing, it rotates towards the absorption tower under the action of water flow.

[0019] The beneficial effects of this utility model are reflected in:

[0020] This invention not only accurately measures the density of the absorption tower, but also enables periodic sampling, rinsing, and backwashing, effectively reducing the economic costs of replacement of worn spare parts and regular equipment maintenance. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the non-contact density measuring device for desulfurization absorption towers according to this utility model.

[0022] Figure 2 This is a schematic diagram of the unblocking component of this utility model.

[0023] Explanation of reference numerals in the attached figures:

[0024] 1. Absorption tower; 2. Density meter measuring tank; 21. Positive pressure side sampling port; 22. Negative pressure side sampling port; 3. Differential pressure transmitter; 31. Positive pressure side; 32. Negative pressure side; 4. Defoaming box; 5. Sampling pipeline; 51. Manual sampling door; 52. Electric sampling door; 6. Main flushing pipeline; 61. Branch flushing pipeline; 62. Overflow pipe; 63. Manual flushing water door; 64. Electric flushing water door; 65. Manual backflushing sampling door; 7. Discharge pipeline; 71. Electric discharge door; 8. DCS system; 9. Unblocking components; 91. Rotating rod; 92. Unblocking rod; 93. Guide plate. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present utility model, and not all of them. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model.

[0026] Please see Figure 1 and Figure 2 This utility model provides a non-contact density measuring device for desulfurization absorption towers, including an absorption tower 1, a density meter measuring barrel 2, a differential pressure transmitter 3, and a defoaming box 4.

[0027] Absorption tower 1 is connected to densitometer measuring tank 2 via sampling pipeline 5. Differential pressure transmitter 3 has a positive pressure side 31 and a negative pressure side 32, which are connected to densitometer measuring tank 2 via pipelines. Densitometer measuring tank 2 has a positive pressure side sampling port 21 and a negative pressure side sampling port 22, with a distance h between the positive pressure side sampling port 21 and the negative pressure side sampling port 22. Defoaming box 4 is located on top of densitometer measuring tank 2. Differential pressure transmitter 3 is connected to DCS system 8. DCS system is a widely used technology in this field and is readily available, so it will not be described in detail here.

[0028] In this embodiment, after the slurry to be tested fills the entire density meter measuring tank 2 and the defoaming box 4, the pressure at the center of the negative pressure sampling port 22 and the positive pressure sampling port 21 of the differential pressure transmitter 3 can be used to read the value of ΔP of the differential pressure transmitter 3. The density of the slurry to be tested can be obtained by calculation as follows:

[0029] ΔP=ρ*g*h 1

[0030] ρ=ΔP / g*h2

[0031] In formulas 1 and 2: ΔP is the reading of the diaphragm differential pressure transmitter 3; ρ is the slurry density; g is the acceleration due to gravity; and h is the center distance between the positive and negative pressure sides of the diaphragm differential pressure transmitter 3.

[0032] Specifically, the sampling pipeline 5 is equipped with a manual sampling door 51 and an electric sampling door 52.

[0033] In one embodiment, a flushing main line 6 is also included for flushing the slurry in the line after measurement.

[0034] The main flushing pipeline 6 includes a flushing branch pipeline 61 connected to the sampling pipeline 5 and an overflow pipe 62 connected to the defoaming box 4. The flushing branch pipeline 61 is equipped with a manual flushing water valve 63, an electric flushing water valve 64, and a manual backwashing sampling valve 65 in sequence.

[0035] In one embodiment, it also includes a discharge pipe 7 connected to the densitometer measuring tank 2, and the discharge pipe 7 is provided with a discharge electric gate 71.

[0036] In one embodiment, diaphragms 23 are provided at both the positive pressure sampling port 21 and the negative pressure sampling port 22 to prevent corrosion of the transmitter and sampling pipeline by the slurry.

[0037] It should be noted that both the manual and electric doors mentioned above can use equipment commonly found in this field, as long as it can achieve the opening and closing of the pipeline.

[0038] In one embodiment, the sampling pipeline 5 is provided with a dredging component 9 near the outlet of the absorption tower 1. The dredging component 9 includes a rotating rod 91, one end of which is hinged to the inner wall of the sampling pipeline 5, and the other end is fixedly connected to a dredging rod 92. A guide plate 93 is provided at the connection end between the rotating rod 91 and the dredging rod 92.

[0039] In this embodiment, when the sampling pipeline 5 is flushed, the water in the main flushing pipeline 6 enters the absorption tower 1 through the sampling pipeline 5. During the process, the water flow will impact the guide plate 93, causing the guide plate 93 to push the rotating rod 91 to rotate towards the outlet of the absorption tower 1. The unblocking rod 92 on it can then unblock the slurry blocking the pipeline, avoiding the problem that the water flow cannot effectively flush the pipeline due to severe blockage.

[0040] In one embodiment, multiple rotating rods 91 are arranged circumferentially within the sampling pipeline 5. This arrangement in this embodiment improves the unblocking effect through the multiple rotating rods 91.

[0041] In one embodiment, the rotating rod 91 is initially attached to the inner wall of the sampling pipeline 5, and rotates towards the absorption tower 1 under the action of water flow when the pipeline is flushed.

[0042] The device has the following functions:

[0043] Slurry sampling: This part of the design includes the slurry sampling port of the absorption tower, manual sampling door 51, electric sampling door 52, and manual backwashing sampling door 65. The function of this part is to complete the slurry sampling of the absorption tower. The sampling process is as follows: the slurry from the sampling port passes through the manual sampling door 51, the electric sampling door 52, and the manual backwashing sampling door 65 in sequence and then enters the density meter measuring tank 2 and the slurry defoaming tank 4. After the slurry is filled, the sampling door is closed.

[0044] Non-contact slurry density measurement: This part of the device includes a densitometer measuring tank 2, a defoaming tank 4, and a differential pressure transmitter 3. The main function of this device is to hold static slurry. As shown in the figure, its main function is to eliminate air bubbles in the slurry and provide information on slurry sediment during the measurement process. The design incorporates anti-slurry wall adhesion features. The device and its components utilize a diaphragm device to prevent corrosion of the transmitter and sampling pipeline by the slurry. The design function of this part is to perform differential pressure measurement on the static slurry contained in the densitometer measuring tank 2 and the defoaming tank 4, and then transmit the data to the DCS system 8. The measurement process is as follows: When the slurry enters the density meter measuring tank 2 and the defoaming box 4 through the slurry sampling pipeline 5 and passes through the overflow pipe flange, the sampling electric door 52 is closed. After the sampling electric door 52 is closed, the slurry bubbles inside the device begin to precipitate and settle. When the settled part enters the density meter measuring tank 2 in an orderly manner, the differential pressure tends to stabilize. At this time, the slurry is transferred to the density meter measuring tank 2 and the defoaming box 4 through the sampling pipe. The device measures the stable differential pressure and sends it to the DCS system 8.

[0045] Sample and Rinse Water Discharge: This section of the device includes a manual rinse water valve 63, an electric rinse water valve 64, a manual backwash sampling valve 65, a densitometer measuring tank 2, a defoaming tank 4, an overflow pipe 62, and an electric discharge valve 71. The function of this section is to completely drain the slurry and rinse water from the densitometer measuring pipeline and each device, preparing for the next sampling and measurement. Rinse and Discharge Process: After the densitometer measurement is completed, the slurry in the densitometer measuring tank 2 and the defoaming tank 4 is discharged into the trench through the electric discharge valve 71. After discharge, the electric discharge valve 71 is closed, and simultaneously the manual rinse water valve 63 and the electric rinse water valve 64 are opened. The rinse water flows sequentially through the manual backwash sampling valve 65, then into the densitometer measuring tank 2, the defoaming tank 4, and the overflow pipe 62 before flowing into the trench. After closing the manual rinse water valve 63 and the electric rinse water valve 64, the electric discharge valve 71 is opened. After the rinse water discharge is complete, the electric discharge valve 71 is closed.

[0046] Anti-clogging sampling backwashing: This part of the device includes a manual flushing water door 63, an electric flushing water door 64, a manual sampling door 51, an electric sampling door 52, and a manual backwashing sampling door 65. The design function of this part is to address the possibility of sedimentation when the manual doors are open for extended periods, leading to slurry accumulation in the pipes before the manual doors. Prolonged sedimentation can cause blockage of the sampling tube, preventing normal sampling and measurement. Backwashing process: After exiting the densitometer measurement state, close the manual backwashing sampling door 65, open the manual sampling door 51 and the electric sampling door 52, and open the manual flushing water door 63 and the electric flushing water door 64. The high-pressure water slurry and sediment are then pumped back into the absorption tower 1, completing the anti-clogging backwashing.

[0047] It should be noted that if the embodiments of this utility model involve directional indicators such as up, down, left, right, front, back, etc., the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture as shown in the attached figure. If the specific posture changes, the directional indicators will also change accordingly.

[0048] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied. Furthermore, "multiple" refers to two or more. Moreover, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent.

[0049] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A non-contact density measuring device for a desulfurization absorption column, characterized by: It includes an absorption tower (1), a density meter measuring tank (2), a differential pressure transmitter (3), and a defoaming box (4); The absorption tower (1) is connected to the densitometer measuring barrel (2) through the sampling pipeline (5). The differential pressure transmitter (3) has a positive pressure side (31) and a negative pressure side (32). The positive pressure side (31) and the negative pressure side (32) are connected to the densitometer measuring barrel (2) through pipelines. The densitometer measuring barrel (2) has a positive pressure side sampling port (21) and a negative pressure side sampling port (22). The positive pressure side sampling port (21) and the negative pressure side sampling port (22) are spaced apart by a distance h. The defoaming box (4) is located on the top of the densitometer measuring barrel (2). The differential pressure transmitter (3) is connected to the DCS system (8).

2. The non-contact density measurement device for a desulfurization absorption column according to claim 1, characterized by: The sampling pipeline (5) is equipped with a manual sampling door (51) and a sampling electric door (52).

3. The non-contact density measurement device for a desulfurization absorption column according to claim 1, characterized by: It also includes a flushing main pipeline (6) for flushing the slurry in the pipeline after measurement.

4. The non-contact density measurement device for a desulfurization absorption column according to claim 3, characterized by: The main flushing pipeline (6) includes a flushing branch pipeline (61) connected to the sampling pipeline (5) and an overflow pipe (62) connected to the defoaming box (4). The flushing branch pipeline (61) is provided with a manual flushing water valve (63), an electric flushing water valve (64), and a manual backwashing sampling valve (65) in sequence.

5. The non-contact density measurement device for a desulfurization absorption column according to claim 1, characterized by: It also includes a discharge pipe (7) connected to the density meter measuring barrel (2), and the discharge pipe (7) is equipped with a discharge electric gate (71).

6. The non-contact density measurement device for a desulfurization absorption column according to claim 1, characterized by: A diaphragm (23) is provided at both the positive pressure side sampling port (21) and the negative pressure side sampling port (22).

7. The non-contact density measurement device for a desulfurization absorption column according to claim 4, characterized by: The sampling pipeline (5) is provided with a dredging component (9) near the outlet of the absorption tower (1). The dredging component (9) includes a rotating rod (91). One end of the rotating rod (91) is hinged to the inner wall of the sampling pipeline (5), and the other end is fixedly connected to a dredging rod (92). The connecting end of the rotating rod (91) and the dredging rod (92) is provided with a guide plate (93).

8. The non-contact density measurement device for a desulfurization absorption column according to claim 7, characterized by: The rotating rod (91) is provided in multiple circumferentially spaced positions within the sampling pipeline (5).

9. The non-contact density measurement device for a desulfurization absorption column according to claim 7, characterized by: In its initial state, the rotating rod (91) is attached to the inner wall of the sampling pipeline (5). When the pipeline is flushed, it rotates towards the absorption tower (1) under the action of water flow.

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