Split type high-temperature exhaust oxygen content on-line monitoring system

Abstract

The utility model relates to the technical field of flue gas oxygen content and concentration detection, in particular to a split type high-temperature exhaust gas oxygen content on-line monitoring system which comprises a sampling probe and a sampling box, the sampling probe is installed in a hollow sleeve, the hollow sleeve is connected with a secondary combustion chamber, a gas outlet is formed in the hollow sleeve and connected with a gas inlet of a settling tank, and the sampling box is connected with a gas outlet of the settling tank. A gas outlet of the settling tank is connected with a gas inlet of the measuring tank, a gas outlet of the measuring tank is connected with a gas inlet of the sampling box, a zirconium oxide detector is mounted on the measuring tank, a probe of the zirconium oxide detector extends into the measuring tank, the zirconium oxide detector is connected with a zirconium oxide oxygen analyzer through a wire, and the gas inlet of the sampling box is connected with a sampling pipe; the sampling pipe is sequentially connected with a primary filter, a secondary filter and a sampling pump which are arranged in the sampling box. According to the utility model, the settling tank is additionally arranged, so that particles and condensed water in flue gas can be settled at the bottom of the tank, regular cleaning is facilitated, a split type design is adopted, a blocked pipeline is convenient to replace, and the sampling pump can keep the sampling flow constant.

Description

Technical Field

[0001] The utility model relates to the technical field of oxygen concentration detection in flue gas, in particular to a split type high-temperature exhaust oxygen content online monitoring system. Background Art

[0002] When solid waste is incinerated, air is a combustion aid. Effectively controlling the oxygen content in the combustion furnace can achieve the goal of reducing energy consumption.

[0003] At present, the direct-insertion zirconium oxide analyzer is generally inserted into the secondary combustion chamber, and the compressed air jet pump is used for sampling. Specifically, the compressed air jet pump adopts the siphon principle, that is, a high-speed airflow through a horn forms a siphon negative pressure at the pipe mouth, and the gas in the secondary combustion chamber is sucked out after siphoning. After the gas is sucked out, it passes through the jet pump to generate siphoning, and the high-temperature gas inside is sampled out. After measurement and analysis by the zirconium oxide analyzer, there are several problems:

[0004] (1) The temperature inside the secondary combustion chamber is high, the minimum operating temperature is ≥1100 degrees, and the probe of the direct-insertion zirconia analyzer will burn out;

[0005] (2) The injection volume of the jet pump cannot achieve steady flow and constant pressure because it is controlled by air pressure. If the compressed air changes during industrial use, the injection negative pressure will also change, and the suction force will change. It is difficult to accurately adjust the appropriate injection volume during the use of compressed air. The injection volume reflects quickly and is easy to cause blockage. Because the negative pressure sucked in is large, more sampled gas will come in, and at the same time, more dust will be carried by the sampled gas, which will cause blockage of the entire system;

[0006] (3) If the injection gas flow rate is reduced, the sampling sensitivity will be low, and the sampling gas will be less, so it is impossible to accurately control the gas flow rate during the entire sampling process, and it is impossible to ensure the accuracy, precision and timeliness of the measurement;

[0007] (4) When hot air comes into contact with cold air, condensation will occur, and condensed water will be produced. Condensed water will damage the measuring equipment, and the chemical reaction cannot be timely converted into electrical signals, thus affecting the accuracy of the measurement.

[0008] (5) It becomes clogged after 3-7 days of use and needs to be repaired. The sensitivity cannot be adjusted accurately and needs to be adjusted frequently, which is subject to many external interference factors.

[0009] (6) Integrated equipment cannot be effectively cleared once blocked, and the zirconia probe can only be replaced with a new one after being contaminated, which is costly and expensive. Utility Model Content

[0010] The technical problem to be solved by the utility model is to overcome the deficiencies in the prior art and provide a split type high temperature exhaust oxygen content online monitoring system.

[0011] The technical solution adopted by the utility model to solve its technical problems is: a split type high-temperature air extraction oxygen content online monitoring system, including a sampling probe and a sampling box, the sampling probe is installed in a hollow casing, the hollow casing is connected to the secondary combustion chamber, an air outlet is provided on the hollow casing, the air outlet is connected to the air inlet of a sedimentation tank, the air outlet of the sedimentation tank is connected to the air inlet of a measuring tank, the air outlet of the measuring tank is connected to the air inlet of the sampling box, a zirconia detector is installed on the measuring tank, the probe of the zirconia detector extends into the measuring tank, the zirconia detector is connected to the wire of the zirconia oxygen analyzer, the air inlet of the sampling box is connected to a sampling tube, the sampling tube is sequentially connected to a primary filter, a secondary filter and a sampling pump placed in the sampling box, and the discharge port of the sampling pump is connected to a discharge pipe.

[0012] Furthermore, a connector connected to the hollow sleeve is fixed on the secondary combustion chamber, and the connector has a mounting flange. Both ends of the hollow sleeve are provided with flange edges, the flange edge at one end is connected to the mounting flange, and the flange edge at the other end is connected to the mounting surface of the sampling probe.

[0013] Furthermore, an air outlet is provided on the peripheral wall of the hollow sleeve close to the mounting surface of the sampling probe, and an outlet pipe is connected to the air outlet.

[0014] Furthermore, the sedimentation tank comprises an upper cover, a tank body and a bottom cover, the tank body comprises an outer tank and an inner tank, and a cavity is formed between the inner tank and the outer tank. The sedimentation tank is configured in this way to collect and store settled particles and condensed water.

[0015] Furthermore, the air inlet and the air outlet of the sedimentation tank are both arranged on the upper cover.

[0016] Furthermore, the measuring tank comprises a base, a tank body and a mounting cover, a supporting tube for supporting the outer shell of the zirconia detector is fixed on the mounting cover, and a probe of the zirconia detector passes through the supporting tube and enters into the tank body.

[0017] Furthermore, the zirconia oxygen analyzer is installed on a support column close to the secondary combustion chamber, and a sampling box is installed on the support column above the zirconia oxygen analyzer.

[0018] Furthermore, the primary filter and the secondary filter are arranged side by side in the middle of the sampling box, the sampling pump is installed on the upper part of the sampling box and close to the secondary filter, and a switch is installed on one side of the sampling pump. This arrangement prevents filtered particles and liquids from entering the sampling pump, thereby extending the service life of the sampling pump.

[0019] Furthermore, the zirconium oxide oxygen analyzer has a display screen that is remotely transmitted to a DCS or a data acquisition system and displays oxygen content and temperature information.

[0020] The beneficial effects of the utility model are:

[0021] (1) The sampling probe of the utility model is installed in a hollow casing, and a cavity is formed in the hollow casing to prevent the sampling probe from being directly inserted into the secondary combustion chamber and causing the probe to burn;

[0022] (2) The utility model adds a sedimentation tank, and the particles and condensed water in the flue gas will settle at the bottom of the tank. The split design makes it easy to replace the pipeline blockage, and the sampling pump can maintain a constant sampling flow rate. The sedimentation tank is used to initially settle the large particles and condensed water in the flue gas, which will not pollute the zirconium oxide detector;

[0023] (3) The sedimentation tank of the utility model is connected to the measuring tank, and the probe of the zirconium oxide detector is installed in the measuring tank. What is measured is the gas after the initial sedimentation, which has no particulate matter and condensed water, is not subject to external interference, and has no interference from chemical-to-electric conversion, so the accuracy of the measurement is guaranteed;

[0024] (4) After filtering through the primary filter and the secondary filter, cleaner gas is obtained and the gas enters the sampling pump. The purpose of the sampling pump is to maintain constant flow and pressure to ensure that the flow through the measuring tank is stable and constant, and will not interfere with the sensitivity of the analyzer. It can timely reflect the actual oxygen content of the measured gas and discharge it into the air or return it to the furnace. The gas after the secondary filtration is relatively clean and also protects the sampling pump.

[0025] (5) The monitoring system of the utility model can be adjusted once every 2-3 months, which saves costs, improves accuracy, and prolongs the maintenance cycle. In addition, the gas after passing through the sampling pump is pollution-free and can be sent back to the secondary combustion chamber through the pipeline;

[0026] (6) The metal parts of the entire system are made of 316L material to delay corrosion. Due to the split installation design, damaged parts can be replaced in a timely manner and costs can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The utility model is further described below in conjunction with the accompanying drawings and implementation modes.

[0028] Figure 1 It is a structural schematic diagram of the utility model.

[0029] Figure 2 It is a schematic diagram of the installation of the sampling probe in the utility model.

[0030] Figure 3 It is a schematic diagram of the internal structure of the sedimentation tank in the utility model.

[0031] Figure 4 It is a schematic diagram of the internal structure of the measuring tank in the utility model.

[0032] Figure 5 The utility model is a gas sampling flow chart.

[0033] In the figure: 1. sampling probe, 2. sampling box, 3. hollow sleeve, 31. flange edge, 4. sedimentation tank, 41. upper cover, 42. tank body, 421. outer tank, 422. inner tank, 43. bottom cover, 5. measuring tank, 51. base, 52. tank body, 53. installation cover, 54. support tube, 6. zirconium oxide detector, 7. zirconium oxide oxygen analyzer, 71. display screen, 8. sampling tube, 9. primary filter, 10. secondary filter, 11. sampling pump, 12. discharge pipe, 13. secondary combustion chamber, 14. connector, 141. installation flange, 15. switch, 16. support column. DETAILED DESCRIPTION

[0034] The present invention is now further described in conjunction with the accompanying drawings. These drawings are simplified schematic diagrams that only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0035] like Figure 1 and Figure 2 As shown, a split type high-temperature exhaust oxygen content online monitoring system includes a sampling probe 1 and a sampling box 2, the sampling probe 1 is installed in a hollow sleeve 3, the hollow sleeve 3 is connected to the secondary combustion chamber 13, an air outlet is provided on the hollow sleeve 3, the air outlet is connected to the air inlet of the settling tank 4, the air outlet of the settling tank 4 is connected to the air inlet of the measuring tank 5, the air outlet of the measuring tank 5 is connected to the air inlet of the sampling box 2, a zirconia detector 6 is installed on the measuring tank 5, the probe of the zirconia detector 6 extends into the measuring tank 5, the zirconia detector 6 is connected to the zirconia oxygen analyzer 7 by wire, the air inlet of the sampling box 2 is connected to the sampling tube 8, the sampling tube 8 is connected to the primary filter 9, the secondary filter 10 and the sampling pump 11 placed in the sampling box 2 in sequence, the discharge port of the sampling pump 11 is connected to the discharge pipe 12, the discharge pipe 12 can be connected to the secondary combustion chamber 4, and can also be discharged into the air. Among them, the primary filter 9 and the secondary filter 10 are arranged side by side in the middle of the sampling box 2, the sampling pump 11 is installed on the upper part of the sampling box 2 and close to the secondary filter 10, and a switch 15 is also installed on one side of the sampling pump 11. The zirconia oxygen analyzer 7 is installed on a support column 16 close to the secondary combustion chamber 13, and the sampling box 2 is installed on the support column 16 above the zirconia oxygen analyzer 7. The zirconia oxygen analyzer 7 has a display screen 71 that is remotely transmitted to a DCS (distributed control system) or a data acquisition system and displays oxygen content and temperature information.

[0036] like Figure 2As shown, a connector 14 connected to the hollow sleeve 3 is fixed on the secondary combustion chamber 13, and the connector 14 has a mounting flange 141. Both ends of the hollow sleeve 3 are provided with flange edges 31, and the flange edge 31 at one end is connected to the mounting flange 141, and the flange edge 31 at the other end is connected to the mounting surface of the sampling probe 1. An air outlet is provided on the peripheral wall of the hollow sleeve 3 close to the mounting surface of the sampling probe 1, and a lead-out pipe 32 is connected to the air outlet.

[0037] like Figure 3 As shown, the settling tank 4 comprises an upper cover 41, a tank body 42 and a bottom cover 43. The tank body 42 comprises an outer tank 421 and an inner tank 422. A cavity is formed between the inner tank 422 and the outer tank 421. The air inlet and the air outlet of the settling tank 4 are both arranged on the upper cover 41.

[0038] like Figure 4 As shown, the measuring tank 5 includes a base 51 , a tank body 52 and a mounting cover 53 , on which a support tube 54 for supporting the outer shell of the zirconia detector 6 is fixed, and a probe of the zirconia detector 6 passes through the support tube 54 and enters into the tank body 52 .

[0039] The basic principle of the zirconia oxygen analyzer 7 is: zirconia is used as a solid electrolyte, and the oxygen concentrations on both sides of the electrolyte are different at high temperature to form a concentration cell. The potential generated by the concentration cell is related to the oxygen concentrations on both sides. If the oxygen concentration on one side is fixed, the oxygen content on the other side can be measured by measuring the output potential. At a high temperature of 600-1200°C, the zirconia material calcined at high temperature has good conductivity for oxygen ions. When the oxygen concentrations on both sides of the zirconia tube are not equal, the oxygen molecules on the side with a large concentration combine with two electrons on the surface electrode of the zirconia tube on that side to form oxygen ions, and then migrate to the side with a low oxygen concentration through the oxygen ion holes in the zirconia material lattice. When it reaches the side with a low concentration, two electrons are released on the electrode on that side to form oxygen molecules, so that charge accumulation is caused on the electrode, and a potential is generated between the two electrodes. This potential hinders the further progress of this migration until a dynamic equilibrium state is reached, thus forming a concentration cell. The potential generated by it is related to the oxygen concentration difference on both sides, which is called a concentration potential. The generated potential has a fixed relationship with the working temperature of the oxidation tube and the oxygen concentration on both sides. If the reference gas concentration is known, the oxygen concentration of the measured gas can be calculated based on the oxygen potential on both sides of the zirconia tube and the operating temperature of the zirconia tube.

[0040] like Figure 5As shown, the specific working principle is: the sampling probe 1 can measure the temperature in the secondary combustion chamber 13, and the gas reaches the sedimentation tank 4 through the hollow sleeve 3 for sedimentation. The particles and condensed water in the flue gas will settle at the bottom of the tank. The gas reaches the measuring tank 5, and after detection by the zirconia detector 6, the data is transmitted to the zirconia oxygen analyzer 7. After conversion by the zirconia oxygen analyzer 7, the temperature, oxygen content and other information are displayed on the display screen 71. The gas is then filtered by the primary filter 9 and the secondary filter 10 to be cleaner. The gas enters the sampling pump 11. The sampling pump 11 ensures constant flow and pressure of the gas during the whole process. The gas after passing through the sampling pump 11 is basically pollution-free and can be sent back to the secondary combustion chamber 13 through the pipeline.

[0041] In addition, all components in the split high-temperature exhaust oxygen content online monitoring system of this embodiment are arranged close to each other, which is convenient for installation, repair and maintenance. All pipelines are made of high-temperature and corrosion-resistant materials, and the pipeline interfaces are all made of ferrule-type pipe joints to prevent leakage and measurement errors.

[0042] The above-mentioned implementation mode is only for illustrating the technical concept and features of the utility model, and its purpose is to enable people familiar with this technology to understand the content of the utility model and implement it. It cannot be used to limit the protection scope of the utility model. All equivalent changes or modifications made according to the spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. A split type high temperature exhaust oxygen content online monitoring system, comprising a sampling probe and a sampling box, characterized in that: The sampling probe is installed in a hollow casing, which is connected to the secondary combustion chamber. An air outlet is provided on the hollow casing, which is connected to the air inlet of a sedimentation tank, which is connected to the air inlet of a measuring tank, which is connected to the air inlet of a sampling box. A zirconia detector is installed on the measuring tank, and the probe of the zirconia detector extends into the measuring tank. The zirconia detector is connected to the wire of a zirconia oxygen analyzer. The air inlet of the sampling box is connected to a sampling tube, which is sequentially connected to a primary filter, a secondary filter and a sampling pump placed in the sampling box, and the discharge port of the sampling pump is connected to a discharge pipe.

2. The split type high temperature exhaust oxygen content online monitoring system according to claim 1 is characterized in that: A connector connected to the hollow sleeve is fixed on the secondary combustion chamber, and the connector has a mounting flange. Both ends of the hollow sleeve are provided with flange edges, the flange edge at one end is connected to the mounting flange, and the flange edge at the other end is connected to the mounting surface of the sampling probe.

3. The split type high temperature exhaust oxygen content online monitoring system according to claim 2 is characterized in that: An air outlet is arranged on the peripheral wall of the hollow sleeve close to the mounting surface of the sampling probe, and an outlet pipe is connected to the air outlet.

4. The split type high temperature exhaust oxygen content online monitoring system according to claim 1 is characterized in that: The sedimentation tank comprises an upper cover, a tank body and a bottom cover. The tank body comprises an outer tank and an inner tank. A cavity is formed between the inner tank and the outer tank.

5. The split type high temperature exhaust oxygen content online monitoring system according to claim 4 is characterized in that: The air inlet and the air outlet of the sedimentation tank are both arranged on the upper cover.

6. The split type high temperature exhaust oxygen content online monitoring system according to claim 1 is characterized in that: The measuring tank comprises a base, a tank body and a mounting cover, a supporting tube for supporting the outer shell of the zirconium oxide detector is fixed on the mounting cover, and a probe of the zirconium oxide detector passes through the supporting tube and enters into the tank body.

7. The split type high temperature exhaust oxygen content online monitoring system according to claim 1 is characterized in that: The zirconia oxygen analyzer is installed on a support column close to the secondary combustion chamber, and a sampling box is installed on the support column above the zirconia oxygen analyzer.

8. The split type high temperature exhaust oxygen content online monitoring system according to claim 1 is characterized in that: The primary filter and the secondary filter are arranged side by side in the middle of the sampling box, the sampling pump is installed on the upper part of the sampling box and close to the secondary filter, and a switch is also installed on one side of the sampling pump.

9. The split type high temperature exhaust oxygen content online monitoring system according to claim 1 is characterized in that: The zirconium oxide oxygen analyzer has a display screen that is remotely transmitted to a DCS or a data acquisition system and displays oxygen content and temperature information.

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