Dry quenching analyzer negative pressure detection protection device

Abstract

The utility model discloses a negative pressure detection protection device for a dry quenching analyzer, belongs to the field of dry quenching analyzers, and solves the problem of back flushing of nitrogen when a program control electromagnetic valve breaks down. The device comprises a program control processor, an intermediate relay, an intelligent digital display instrument and a differential pressure transmitter, the program control processor is respectively connected with a nitrogen purging solenoid valve, a sample gas cut-off solenoid valve and a vacuum breaking solenoid valve of the dry quenching analyzer through the intermediate relay, and the differential pressure transmitter is connected with the intermediate relay through the intelligent digital display instrument. The negative pressure end of the differential pressure transmitter is connected to the sample gas suction end of a demineralized water jet pump of the dry quenching analyzer, and the positive pressure end of the differential pressure transmitter is directly communicated with the atmosphere. And when the negative pressure detected by the differential pressure transmitter reaches a certain value, the intelligent digital display instrument performs interlocking action, so that the intermediate relay reversely rotates to cut off the operation of the program control processor, the nitrogen purging electromagnetic valve and the sample gas cut-off electromagnetic valve are closed, the vacuum breaking electromagnetic valve is opened, and the negative pressure over-limit automatic protection function of the analyzer system is realized.

Description

Technical Field

[0001] The utility model belongs to the field of dry coke quenching analyzers, and in particular relates to a negative pressure detection and protection device for dry coke quenching analyzers. Background Art

[0002] The coking dry quenching multi-component gas analyzer plays a very important role in the production process. The inert circulating gas exchanges heat with the coke in the countercurrent in the cooling section of the dry quenching coke oven, and enters the dry quenching boiler after the temperature rises to 900℃~960℃. Because a small amount of air will leak into the negative pressure section of the gas circulation system, O 2 It will react with coke through the red coke layer to generate CO 2 , CO 2 In the high temperature area of ​​the coke layer, it will be reduced to CO. As the number of cycles increases, the CO concentration in the circulating gas becomes higher and higher. In addition, the residual volatile matter in the coke is always precipitating, and the H generated by the pyrolysis of the coke 2 , CO, CH 4 etc. are also flammable and explosive components. Therefore, during the CDQ operation, the concentration of combustible components in the circulating gas must be controlled below the explosion limit. Generally, there are two measures to control this. First, continuously add an appropriate amount of industrial N to the gas circulation system. 2 The first method is to dilute the combustible components in the circulating gas and then release the corresponding amount of circulating gas; the second method is to continuously introduce a proper amount of air into the circulating gas heated to 900℃~960℃ to burn the increased combustible components, and then release the corresponding amount of circulating gas after the boiler cools down. Both methods can be used to measure the H in the circulating gas by the automatic online gas analyzer installed on the circulating gas pipeline. 2 , CO concentration to feedback regulation. Magnetic flow oxygen analyzer is used to detect the oxygen content in the circulating gas, and thermal conductivity gas analyzer is used in the dry coke quenching device to analyze the H in the circulating gas. 2 The general infrared analyzer is used to analyze the CO and CO in the circulating gas in the dry coke quenching device. 2 The gas content is determined by the infrared light beam emitted by the infrared generating device penetrating the sample gas, and the component content of the sample gas is calculated based on the amount of infrared light absorbed. Therefore, the measurement results of the circulating gas analyzer are very important, requiring accuracy, real-time and continuous measurement. The utility model mainly studies and solves the problems existing in the pre-sampling device of the current analyzer, which has very important practical significance.

[0003] For many years, in the actual application of the CDQ analyzer system, the automatic purge system of the gas analyzer uses a programmable solenoid valve to switch according to the processor timing to achieve system purge. In the actual operation, nitrogen is used to purge the sampling pipeline and the sample gas chamber. When the programmable solenoid valve fails, nitrogen backflush will occur, blowing desalted water into the measurement room of the multi-component analyzer, causing damage to expensive analytical instruments and affecting the continuous, stable and accurate online operation of the analyzer. Therefore, it is necessary to invent a negative pressure detection and protection device for the CDQ analyzer. Utility Model Content

[0004] The utility model aims to provide a negative pressure detection and protection device for a dry coke quenching analyzer, so as to solve the problem that when a program-controlled electromagnetic valve fails, nitrogen back-blowing occurs, causing damage to the analyzer.

[0005] The technical scheme of the utility model is: a negative pressure detection and protection device for a dry coke quenching analyzer, comprising a program-controlled processor, an intermediate relay, an intelligent digital display and a differential pressure transmitter, wherein the program-controlled processor is respectively connected with a nitrogen purge solenoid valve, a sample gas cut-off solenoid valve and a vacuum destruction solenoid valve of the dry coke quenching analyzer through the intermediate relay, the differential pressure transmitter is connected with the intermediate relay through the intelligent digital display, the negative pressure end of the differential pressure transmitter is connected to the sample gas suction end of a desalted water jet pump of the dry coke quenching analyzer, and the positive pressure end of the differential pressure transmitter is directly connected to the atmosphere, so as to form a negative pressure detection system.

[0006] As a further improvement of the utility model, the differential pressure transmitter adopts an EJA differential pressure transmitter.

[0007] The beneficial effects of the utility model are as follows: the detection signal of the differential pressure transmitter is connected to the intelligent digital display instrument for display and interlocking, and the interlocking contact action fixed value of the intelligent digital display instrument is set. When the negative pressure detected by the differential pressure transmitter reaches the interlocking contact action fixed value, the intelligent digital display instrument performs an interlocking action, so that the intermediate relay reverses and cuts off the operation of the program-controlled processor, and the nitrogen purge solenoid valve is closed and stops blowing, the sample gas cut-off solenoid valve is closed, and the vacuum destruction solenoid valve is opened, thereby realizing the automatic protection function of the negative pressure over-limit of the analyzer system, preventing nitrogen backblowing, and avoiding water and impurities from entering the analyzer to cause damage to the analyzer, saving the expensive spare parts cost of the analyzer, and ensuring H 2 Analyzer, CO Analyzer, CO 2 Analyzer, O 2 The analyzer operates accurately, in real time and continuously for the analysis of four-component trace gases. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a structural schematic diagram of the utility model.

[0009] In the figure: 1-coke oven; 2-sample gas chamber; 3-primary valve; 4-drain valve; 5-nitrogen purge solenoid valve; 6-vacuum breaking solenoid valve; 7-sample gas cut-off solenoid valve; 8-deionized water jet pump; 9-gas-liquid separator; 10-front stage condenser; 11-cyclone refrigerator; 12-rear stage condenser; 13-float flowmeter; 14-carbon monoxide analyzer; 15-carbon dioxide analyzer; 16-oxygen analyzer; 17-hydrogen analyzer; 18-differential pressure transmitter; 19-intelligent digital display; 20-programmable processor; 21-intermediate relay. DETAILED DESCRIPTION

[0010] The utility model is described in detail below in conjunction with the accompanying drawings.

[0011] Existing CDQ analyzers are as follows: Figure 1 As shown, a sample gas chamber 2 with a diameter of φ80-φ100 is installed on the top of the dry quenching coke oven 1. The sample gas chamber 2 is made of a seamless steel pipe of φ80-φ100 carbon steel or stainless steel. The height of the sample gas chamber 2 is 500mm-1000mm. A seamless steel pipe of φ18-φ20 is used as a sample gas sampling pipeline at the center of the top of the sample gas chamber 2. The sample gas sampling pipeline is connected to a deionized water jet pump 8. A primary valve 3, a nitrogen purge solenoid valve 5, a sample gas cut-off solenoid valve 7, and a vacuum breaking solenoid valve 6 are arranged on the sample gas sampling pipeline from front to back. The nitrogen purge solenoid valve 5 controls the start and stop of nitrogen purge, and the sample gas cut-off solenoid valve 7 is used to cut The sample gas is cut off, and when the sample gas cut-off solenoid valve 7 is closed, the vacuum breaking solenoid valve 6 is opened to break the vacuum negative pressure in the sample gas sampling pipeline; a drain valve 4 is provided between the primary valve 3 and the nitrogen purge solenoid valve 5; a desalted water jet pump 8, a gas-liquid separator 9, a front-stage exhaust condenser 10, a cyclone refrigerator 11, a rear-stage exhaust condenser 12, and a float flowmeter 13 are connected in sequence, and the float flowmeter 13 is respectively connected to a carbon monoxide analyzer 14, a carbon dioxide analyzer 15, an oxygen analyzer 16, and a hydrogen analyzer 17; the condensate reflux pipes of the front-stage exhaust condenser 10 and the rear-stage exhaust condenser 12 are connected to the gas-liquid separator 9, and an overflow pipe is provided on the gas-liquid separator 9.

[0012] The analyzer system is equipped with a 0.7MPa pressure low-pressure instrument nitrogen purge, which can effectively prevent pipeline blockage. The program-controlled processor 20 serves as the command center, sets the purge time according to actual needs, and controls the sample gas cut-off solenoid valve 7, the nitrogen purge solenoid valve 5, and the vacuum breaking solenoid valve 6 to operate in sequence according to the program-controlled processor command sequence. The front end of the analyzer is equipped with a desalted water for sample gas water washing and dehumidification, which can extend the service life of expensive analytical instruments. The jet pressure principle is used to extract the analysis sample gas in the dry quenching coke oven 1. After the desalted water is ejected from the nozzle of the desalted water jet pump 8 at high speed, the gas around the throat inlet of the desalted water jet pump 8 is taken away by the high-speed flowing desalted water to form a vacuum, and the gas in the dry quenching coke oven 1 is sucked in. The two fluids are mixed in the throat and exchange kinetic energy, which increases the kinetic energy of the gas in the dry quenching coke oven 1. Most of the kinetic energy is converted into pressure energy through the diffusion tube. Finally, the desalted water and the mixed sample gas enter the gas-liquid separator 9 together, and the separated desalted water and impurities overflow and are discharged. The gas-liquid separator The dry quenching furnace sample gas released from the top of the separator 9 enters the front-stage condenser 10, and the condensed water of the front-stage condenser 10 flows back to the gas-liquid separator 9. The sample gas then enters the cyclone refrigerator 11, continues to cool down and releases the condensed water, and then enters the rear-stage condenser 12. The condensed water of the rear-stage condenser 12 flows back to the gas-liquid separator 9, and the dry and clean sample gas enters the float flowmeter 13 at a constant flow. Finally, the four-way sample gas is evenly distributed and enters the carbon monoxide analyzer 14, the carbon dioxide analyzer 15, the oxygen analyzer 16, and the hydrogen analyzer 17.

[0013] The utility model adds a negative pressure detection protection device to the existing dry coke quenching analyzer, such as Figure 1 As shown, a negative pressure detection and protection device for a dry coke quenching analyzer comprises a program-controlled processor 20, an intermediate relay 21, an intelligent digital display 19 and a differential pressure transmitter 18. The program-controlled processor 20 is respectively connected to a nitrogen purge solenoid valve 5, a sample gas cut-off solenoid valve 7 and a vacuum breaking solenoid valve 6 of the dry coke quenching analyzer through the intermediate relay 21. The differential pressure transmitter 18 is connected to the intermediate relay 21 through the intelligent digital display 19. The negative pressure end of the differential pressure transmitter 18 is connected to the sample gas suction end of a deionized water jet pump 8 of the dry coke quenching analyzer. The positive pressure end of the differential pressure transmitter 18 is directly connected to the atmosphere to form a negative pressure detection system.

[0014] The differential pressure transmitter 18 adopts the EJA differential pressure transmitter. The EJA differential pressure transmitter adopts a single crystal silicon resonant sensor, which directly outputs a frequency signal. The sensor itself can eliminate the influence of mechanical and electrical interference, changes in ambient temperature and humidity, static pressure and overpressure. Therefore, the EJA differential pressure transmitter has excellent temperature influence characteristics, static pressure influence characteristics, and unidirectional overpressure characteristics. It consists of two parts: a diaphragm box assembly and an electrical conversion assembly. Microelectronic machining technology is used on the single crystal silicon chip to make two H-shaped resonant beams of exactly the same shape and size at the center and edge of its surface, and they are placed in a micro vacuum cavity, so that they are neither in contact with the filling liquid nor affected by air damping during vibration. The silicon resonant beam is in a magnetic field provided by a permanent magnet, and forms a positive feedback loop with a transformer, an amplifier, etc., so that the resonant beam oscillates at high frequency in a self-excited oscillation loop. When the upper and lower surfaces of a single crystal silicon wafer are subjected to pressure and a pressure difference is formed, the silicon wafer will deform, causing the frequency of the center resonance beam to decrease due to compression, and the frequency of the edge resonance beam to increase due to tension, so that the two H-shaped resonance beams feel different strains, resulting in a decrease in the frequency of the center resonance beam due to compression, and an increase in the frequency of the edge resonance beam due to tension, and the difference between the two frequencies corresponds to different pressure signals. The two H-shaped vibration beams on the single crystal silicon resonant sensor convert the pressure or differential pressure signal into a frequency signal and send it to the counter, and then directly transmit the difference between the two frequencies to the CPU for data processing, and convert it into a 4-20mA output signal corresponding to the input signal through D / A. After the signal enters the intelligent digital display 19, negative pressure display and alarm contact interlocking action are performed to realize negative pressure over-limit protection of the analyzer system.

[0015] The utility model adopts a differential pressure transmitter 18 to detect the system negative pressure, and interlocking action protection is used to prevent 0.7MPa pressure nitrogen and deionized water from entering the measuring room of the analyzer. When the vacuum negative pressure exceeds the limit, the purge program is automatically stopped.

[0016] The range of EJA110EDL differential pressure transmitter is set to -20KPa~0KPa, and the interlocking contact action setting value of intelligent digital display 19 is set to -2KPa (1% full scale). When the negative pressure detected by the differential pressure transmitter reaches -2KPa, the intelligent digital display 19 performs interlocking action, so that the intermediate relay 21 reverses and cuts off the operation of the program-controlled processor 20. Then, the nitrogen purge solenoid valve 5 is closed and stopped, the sample gas cut-off solenoid valve 7 is closed, and the vacuum destruction solenoid valve 6 is opened, thereby realizing the automatic protection function of the negative pressure over-limit of the analyzer system to prevent the damage of the analyzer instrument caused by nitrogen backblowing.

Claims

1. A negative pressure detection and protection device for a dry coke quenching analyzer, characterized in that: The invention comprises a program-controlled processor (20), an intermediate relay (21), an intelligent digital display (19) and a differential pressure transmitter (18); the program-controlled processor (20) is respectively connected to a nitrogen purge electromagnetic valve (5), a sample gas cut-off electromagnetic valve (7) and a vacuum breaking electromagnetic valve (6) of a dry coke quenching analyzer via the intermediate relay (21); the differential pressure transmitter (18) is connected to the intermediate relay (21) via the intelligent digital display (19); a negative pressure end of the differential pressure transmitter (18) is connected to a sample gas suction end of a deionized water jet pump (8) of the dry coke quenching analyzer; and a positive pressure end of the differential pressure transmitter (18) is directly connected to the atmosphere.

2. The negative pressure detection and protection device for a dry coke quenching analyzer according to claim 1, characterized in that: The differential pressure transmitter (18) adopts an EJA differential pressure transmitter.

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