Hydrogen chloride concentration detection device and detection method thereof

Abstract

The present invention relates to a hydrogen chloride concentration detection device and a detection method thereof, and belongs to the technical field of hydrogen chloride concentration detection. It comprises a vacuum tank, a vacuum pump is connected to the vacuum tank, an atomizing device is connected to the bottom of the vacuum tank through an air inlet pipe, a blocking cover is provided in the vacuum tank, the atomizing device sprays toward the blocking cover, a nitrogen purge pipe is connected to the vacuum tank, a drainage pipe is provided at the bottom of the vacuum tank, and the drainage pipe is connected to a material box of a spectrophotometer. The present invention effectively improves the detection efficiency of the spectrophotometer, improves the absorption and color development speed of hydrogen chloride, and effectively improves the accuracy of the detection.

Description

Technical Field

[0001] The invention relates to a hydrogen chloride concentration detection device and a detection method thereof, and belongs to the technical field of hydrogen chloride concentration detection. Background Art

[0002] In the process of making catalysts for organic chemical reactions and fine chemical reactions, non-metallic and metallic chlorine-containing compounds will undergo hydrolysis reactions. Hydrochloric acid and free chloride ions will be produced during the hydrolysis reaction. These free chloride ions react with hydrogen ions provided by excess organic acids to produce hydrochloric acid. During the process, hydrogen chloride gas will be produced in the reaction equipment. If there is water in the pipeline or equipment, chloride ions will accelerate the corrosion of the equipment or pipeline in an acidic medium. Therefore, it is necessary to detect the concentration of hydrogen chloride in the reaction device for timely treatment to prevent corrosion of the equipment or pipeline.

[0003] In the existing method for detecting the concentration of hydrogen chloride, air is pumped into the space to be detected, and then a reaction liquid is gradually added to react and develop color, and then the color-developing liquid is added to a spectrophotometer for detection.

[0004] This poses two problems:

[0005] First, currently, gas is obtained from a constant volume space by basically using an air pump to extract gas. This method is difficult to control accuracy. For example, the amount of gas pumped in or the influence of the original gas in the constant volume space on the pumped gas may cause inaccurate detection results.

[0006] Second, this method is relatively inefficient, often using manual testing, and cannot achieve automated continuous testing, nor can it generate sustained and effective continuous data for data support. Summary of the invention

[0007] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art, provide a hydrogen chloride concentration detection device and a detection method thereof, effectively improve the detection efficiency of the spectrophotometer, increase the absorption and color development speed of hydrogen chloride, and effectively improve the detection accuracy.

[0008] The hydrogen chloride concentration detection device described in the present invention includes a vacuum tank, which is connected to a vacuum pump. The bottom of the vacuum tank is connected to an atomizing device through an air inlet pipe. A blocking cover is provided in the vacuum tank. The mist entering the vacuum tank through the atomizing device is sprayed toward the blocking cover. The vacuum tank is connected to a nitrogen purge pipe. A drainage pipe is provided at the bottom of the vacuum tank, and the drainage pipe is connected to a material box of a spectrophotometer.

[0009] The atomizing device of the hydrogen chloride concentration detection device includes a gas flow channel and a liquid storage tank, the liquid storage tank is connected to the gas flow channel, the gas flow channel includes an air intake part, a contraction part and a spray part, the air intake part is connected to the environment to be detected through the electromagnetic valve A, and the other end is connected to the contraction part;

[0010] The liquid storage tank is connected to the side wall of the contraction portion;

[0011] The other end of the contraction part is communicated with the spray part;

[0012] The spray portion extends into the suction can and sprays toward the barrier cap.

[0013] The hydrogen chloride concentration detection device has two vacuum pumps connected to the vacuum tank, namely vacuum pump A and vacuum pump B. Vacuum pump A and vacuum pump B are connected to the vacuum tank through solenoid valve E and solenoid valve F respectively, and are connected to a pressure gauge.

[0014] The hydrogen chloride concentration detection device has three liquid storage bins, two of which are respectively arranged on both sides of the gas flow channel, and the liquid storage bins on both sides are cross-connected to the gas flow channel.

[0015] The hydrogen chloride concentration detection device is provided with two nitrogen purge pipes in the vacuum tank, one of which extends into the vacuum tank from the bottom and blows toward the bottom surface of the blocking cover, and the other enters from the top of the vacuum tank and blows toward the top surface of the blocking cover. The two purge pipes are respectively provided with a solenoid valve C and a solenoid valve D.

[0016] The hydrogen chloride concentration detection device comprises a discharge pipe including a main discharge pipe, a branch discharge pipe and a cleaning pipe, and a solenoid valve group is provided on the discharge pipe. The solenoid valves in the solenoid valve group are respectively installed on the branch discharge pipe and the cleaning pipe and between the adjacent branch discharge pipes corresponding to the main discharge pipe.

[0017] In the hydrogen chloride concentration detection device, a solenoid valve G is provided at the connection between the main discharge pipe and the liquid storage bin.

[0018] The hydrogen chloride concentration detection device is provided with a control device, which receives the signal of the pressure gauge and controls the actions of vacuum pump A, vacuum pump B, solenoid valve A, solenoid valve B, solenoid valve C, solenoid valve D, solenoid valve E, solenoid valve F and the solenoid valve group.

[0019] The method for detecting hydrogen chloride concentration of the present invention,

[0020] Step 1: Vacuum the vacuum tank;

[0021] Step 2: Open the valve and use the negative pressure in the vacuum tank to spray the gas and reaction liquid in the detection environment into the vacuum tank in the form of water mist;

[0022] Step 3: After the water mist settles and reacts to develop color, the color-developing liquid is blown into the material box of the spectrophotometer using the positive pressure formed by nitrogen purge;

[0023] Step 4: Detect by spectrophotometer to obtain the concentration of hydrogen chloride.

[0024] In the method for detecting hydrogen chloride concentration, the color-developing liquid blown out by the vacuum tank each time enters different material slots of the spectrophotometer material box, and the material box is directly replaced after each material slot is full, and the full material box is loaded into the spectrophotometer to form a concentration change curve.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The present invention uses a method of pumping a vacuum tank to a fixed vacuum degree, and through negative pressure, the vacuum tank automatically extracts the gas to be tested in the environment. During the inhalation process, the high-speed flowing gas to be tested forms a negative pressure to draw out the color-developing solvent in the liquid storage tank and bring it into the vacuum tank. However, when extracting, the fast-flowing gas collides with the extracted liquid, forming a mist, which quickly reacts to develop color and collides to block the cover from falling. After collection, detection is performed, and detection can be performed continuously. This detection method will not cause inaccurate detection due to contamination of the previous residual gas in the vacuum tank. At the same time, the control device can control to realize multiple consecutive detections, form multiple detection results in a continuous time, and record experimental data. Not only can the concentration of hydrogen chloride be displayed, but also a curve of the change of hydrogen chloride concentration can be drawn. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the structure of the present invention;

[0028] Figure 2 It is a schematic diagram of the structure of the atomizing device of the present invention;

[0029] Figure 3 It is the vacuum control circuit diagram;

[0030] Figure 4 It is the circuit diagram of the extraction control;

[0031] Figure 5 This is the loading control circuit diagram.

[0032] In the figure, 1, vacuum tank; 2, solenoid valve F; 3, vacuum pump B; 4, blocking cover; 5, solenoid valve A; 6, gas flow channel; 7, solenoid valve B; 8, solenoid valve C; 9, vacuum pump A; 10, solenoid valve E; 11, pressure gauge; 12, material box; 13, material trough; 14, solenoid valve Hb; 15, solenoid valve Ha; 16, solenoid valve Gc; 17, solenoid valve Ga; 18, solenoid valve Gb; 19, spray part; 20, liquid storage tank C; 21, liquid storage tank A; 22, air intake part; 23, liquid storage tank B; 24, contraction part; 25, atomization device; 26, comparator A; 27, second auxiliary power supply; 28 , start switch; 29, first auxiliary power supply; 30, control chip A; 31, relay A; 32, diode; 33, voltage-dividing resistor B; 34, capacitor; 35, relay C; 36, relay D; 37, relay B; 38, comparator B; 39, third auxiliary power supply; 40, solenoid valve D; 41, relay G; 42, relay F; 43, relay E; 44, comparator C; 45, fourth auxiliary power supply; 46, control chip B; 47, relay H; 48, relay I; 49, relay J; 50, relay L; 51, relay K; 52, voltage-dividing resistor A; 53, thyristor. DETAILED DESCRIPTION

[0033] The following is a further description of the hydrogen chloride concentration detection device in conjunction with an embodiment of the present invention:

[0034] like Figure 1-Figure 5 As shown, the hydrogen chloride concentration detection device comprises a vacuum tank 1, and the vacuum tank 1 is connected to a vacuum pump. To ensure energy saving and speed during vacuuming, the present invention sets two-stage vacuum pumps, namely vacuum pump A9 and vacuum pump B3. The vacuuming range of vacuum pump A9 is 1-1×10 -3 Pa, the vacuum range of vacuum pump B3 is 1×10 -3 -1×10 -6 Pa, the bottom of the vacuum tank 1 is connected to an atomizing device 25 through an air inlet pipe, and a blocking cover 4 is provided inside the vacuum tank 1. The mist entering the vacuum tank 1 through the atomizing device 25 is sprayed toward the blocking cover 4. A nitrogen purge pipe is connected to the vacuum tank 1. A drainage pipe is provided at the bottom of the vacuum tank 1. The drainage pipe is connected to the material box 12 of the spectrophotometer. The material box 12 of the spectrophotometer generally has multiple slots, and multiple test samples can be tested at the same time. In this embodiment, a material box 12 is provided, and two material slots 13 are provided in the material box 12.

[0035] The atomizing device 25 of the hydrogen chloride concentration detection device includes a gas flow channel 6 and a liquid storage tank. The liquid storage tank is connected to the gas flow channel 6. The gas flow channel 6 includes an air intake portion 22, a contraction portion 24 and a spray portion 19. The through cross-section of the contraction portion 24 is one-fourth of the air intake portion 22. The spray portion 19 is an open funnel-shaped structure, and a scattering device is provided inside to allow the formed water mist to quickly disperse and enter the vacuum tank 1. The contraction cross-section of the contraction portion 24 is to increase the flow rate. The high-speed flowing gas can extract the liquid in the liquid storage tank and atomize it. The air intake portion 22 is connected to the environment to be detected through the solenoid valve A5, and the other end is connected to the contraction portion 24;

[0036] The liquid storage tank is connected to the side wall of the contraction part 24; the HCl in the drawn gas needs to react with the color-developing liquid in the liquid storage tank to develop color and perform subsequent detection, so when the gas passes through, the reaction liquid is drawn out in sequence and reacts in sequence. Although the speed is very fast, after colliding into tiny droplets, the reaction area is very large and the reaction speed is also very fast. Therefore, the water mist can be colored after being sprayed into the vacuum tank 1. The other end of the contraction part 24 is connected to the spray part 19;

[0037] The spraying part 19 extends into the vacuum tank 1 and sprays toward the blocking cover 4. The blocking cover 4 is suspended on the top of the vacuum tank 1 by a connecting rod, and its shape is an inverted arc structure. In order to make the sprayed water mist turn down and return to the bottom of the arc cover to avoid unimpeded spread to various places in the vacuum tank 1, at the same time, the gas and the droplets collide on the blocking cover 4, and another uniform collision occurs, which is conducive to the reaction of the gas and the droplets.

[0038] The hydrogen chloride concentration detection device has two vacuum pumps connected to the vacuum tank 1, namely vacuum pump A9 and vacuum pump B3. The vacuum pump A9 and vacuum pump B3 are connected to the vacuum tank 1 through solenoid valve E10 and solenoid valve F2 respectively, and are connected to a pressure gauge 11.

[0039] The hydrogen chloride concentration detection device has three liquid storage bins, which are respectively arranged on both sides of the gas flow channel 6, and the liquid storage bins on both sides are cross-connected to the gas flow channel 6. The liquid storage bins are liquid storage bin A21, liquid storage bin B23, and liquid storage bin C20 in order from bottom to top into the contraction part 24.

[0040] The liquid storage tank A21 contains a dilute sodium hydroxide solution;

[0041] The liquid storage bin B23 contains a mercuric thiocyanate solution dissolved in anhydrous ethanol;

[0042] The liquid storage bin C20 contains ammonium ferric sulfate dissolved by perchloric acid;

[0043] The reaction formula of hydrogen chloride gas and color developing solution in the contraction part 24 is:

[0044] 2Cl- +Hg(SCN)2→HgCl2+2SCN - ,

[0045] SCN - +Fe 3+ →Fe(SCN) 2+ (orange-red).

[0046] In the hydrogen chloride concentration detection device, two nitrogen purge pipes are provided in the vacuum tank 1, one of which extends from the bottom of the vacuum tank 1 into the vacuum tank 1 and blows toward the bottom surface of the blocking cover 4, and the other enters from the top of the vacuum tank 1 and blows toward the top surface of the blocking cover 4. The two purge pipes are respectively provided with a solenoid valve C8 and a solenoid valve D40. Since some droplets will remain on the blocking cover 4, the droplets will fall down through the gap between the blocking cover 4 and the side wall of the vacuum tank 1 through purging, and move upward, forming droplets on the side wall of the vacuum tank 1 and the top of the blocking cover 4. In order to avoid contamination of subsequent detection, it is necessary to purge from the top downward.

[0047] The hydrogen chloride concentration detection device comprises a discharge pipe including a main discharge pipe, a branch discharge pipe and a cleaning pipe, and a solenoid valve group is provided on the discharge pipe. The solenoid valves in the solenoid valve group are respectively installed on the branch discharge pipe and the cleaning pipe and between the adjacent branch discharge pipes corresponding to the main discharge pipe.

[0048] In the hydrogen chloride concentration detection device, a solenoid valve G is provided at the connection between the main discharge pipe and the liquid storage bin.

[0049] The hydrogen chloride concentration detection device is provided with a control device, which receives the signal of the pressure gauge 11 and controls the vacuum pump A, vacuum pump B, solenoid valve A5, solenoid valve B7, solenoid valve C8, solenoid valve D40, solenoid valve E10, solenoid valve F2 and the solenoid valve group. The solenoid valve group includes solenoid valve Ga17, solenoid valve Gb18, solenoid valve Gc16, solenoid valve Ha15, and solenoid valve Hb14.

[0050] The control device comprises a vacuum control circuit, an exhaust control circuit and a loading control circuit, and the exhaust control circuit and the loading control circuit are connected to the vacuum control circuit.

[0051] The pumping control circuit includes comparator A26, comparator B38, control chip A30, start switch 28, diode 32, voltage divider resistor A52, voltage divider resistor B33, capacitor 34, relay A31, relay B37, relay C35 and relay D36.

[0052] The signal output end of the pressure gauge 11 is connected to a signal receiving end of the comparator A26 and a signal receiving end of the comparator B38 respectively, the other signal receiving end of the comparator A26 is connected to the second auxiliary power supply 27, and a signal receiving end of the comparator B38 is connected to the third auxiliary power supply 39, the output end of the comparator A26 is connected to one end of the coil of the relay B37 and one end of the coil of the relay C35, and the output end of the comparator B38 is connected to the port A and one end of the coil of the relay D36;

[0053] The connection method of each pin of the control chip A30 is:

[0054] The power supply terminal of the control chip A30 is connected to the first auxiliary power supply 29.

[0055] The P0.1 pin is connected to the first auxiliary power supply 29 through a voltage divider resistor A52 and to ground through a start switch 28.

[0056] The P0.2 pin is connected to Port C,

[0057] The P1.0 pin is connected to the negative pole of the DC power supply through the coil of relay A31, and is connected to the positive pole of the DC power supply through the first normally open contact of relay A31 and the normally closed contact of relay B37.

[0058] The P1.1 pin is connected to Port D,

[0059] P1.2 pin is connected to port E,

[0060] P1.3 pin is connected to Port F,

[0061] The ground terminal of the control chip A30 is grounded;

[0062] One end of the second normally open contact of relay A31 is connected to the positive pole of the AC power supply, and the other end is connected to the negative pole of the AC power supply through the power supply terminal of vacuum pump A9;

[0063] One end of the third normally open contact of relay A31 is connected to the positive electrode of the DC power supply, and the other end is connected to the anode end of diode 32;

[0064] One end of the fourth normally open contact of relay A31 is connected to the positive pole of the DC power supply, and the other end is grounded through the coil of the solenoid valve E10;

[0065] The other end of the coil of relay B37 is grounded;

[0066] One end of the coil of relay C35 is connected to the negative pole of the DC power supply, and the other end of the first normally open contact of relay C35 is connected to the positive pole of the DC power supply through the normally closed contact of relay D36;

[0067] One end of the second normally open contact of relay C35 is connected to the positive pole of the AC power supply, and the other end is connected to the negative pole of the AC power supply through the power supply terminal of the vacuum pump B3;

[0068] One end of the third normally open contact of relay C35 is connected to the positive electrode of the DC power supply, and the other end is connected to the anode end of diode 32;

[0069] One end of the fourth normally open contact of relay D36 is connected to the positive pole of the DC power supply, and the other end is grounded through the coil of the solenoid valve F2;

[0070] The cathode terminal of the diode 32 is connected to the voltage-dividing resistor B33 , the other end of the voltage-dividing resistor B33 is connected to one end of the capacitor 34 and to the port B, and the other end of the capacitor 34 is grounded.

[0071] The extraction control circuit includes comparator C44, relay E43, relay F42 and relay G41.

[0072] One receiving end of the comparator C44 is connected to the fourth auxiliary power supply 45, and the other signal receiving end is connected to the port B.

[0073] One end of the coil of relay E43 is connected to the negative pole of the DC power supply, and the other end is connected to port A and port B through the first normally open contact of relay E43. One end of the second normally open contact of relay E43 is connected to the positive pole of the DC power supply, and the other end is connected to the negative pole of the DC power supply through the coil of solenoid valve A5.

[0074] One end of the coil of relay F42 is connected to the negative pole of the DC power supply, and the other end is connected to port E and connected to the positive pole of the DC power supply through the first normally open contact of relay F42 and the normally closed contact of relay G41. Solenoid valve B7, solenoid valve C8 and solenoid valve D40 are connected to the DC power supply through the second, third and fourth normally open contacts of relay F42 respectively.

[0075] One end of the coil of relay G41 is connected to port F and the other end is connected to the negative pole of the DC power supply.

[0076] The loading control circuit includes control chip B46, relay H47, relay I48, relay J49, relay K51, relay L50,

[0077] The power terminal of the control chip B46 is connected to the auxiliary power supply A, the ground terminal is grounded, the P0.1 pin is connected to the port D, the P1.0 and P1.1 pins are grounded through the coils of the relay H47 and the relay I48 respectively, the P1.2 pin is grounded through the coils of the relay J49 and the relay K51 at the same time, and the P1.3 pin is grounded through the coils of the relay K51 and the relay L50 at the same time;

[0078] Solenoid valve Ga17, solenoid valve Gb18, solenoid valve Gc16, solenoid valve Ha15, and solenoid valve Hb14 are connected to a DC power supply through the normally open contacts of relay H47, relay I48, relay J49, relay K51, and relay L50, respectively.

[0079] The hydrogen chloride detection method of the present invention comprises the following steps: preparing a material box 12, wherein two material troughs 13 are arranged in the material box 12, and using a hydrogen chloride concentration detection device to collect gas. After dissolving the gas with a color developing solution, the gas is injected into the two material troughs 13 of the material box 12 of the spectrophotometer. After a group of material boxes 12 are completely collected, the material box 12 is removed, and the material box 12 is placed in the spectrophotometer for detection. The display is connected to the control chip A30 through the display chip, and the control chip A30 outputs the time when the P0.3 pin receives a signal each time, and the detection results are recorded and a dynamic curve is formed. After a group of material boxes 12 are removed, another group of material boxes 12 is installed for the next group of tests.

[0080] In the hydrogen chloride detection method, the control device records the time each time it sends a signal to the solenoid valve A5, and displays it on the display screen of the control device, forming a dynamic curve through the time and the detection result.

[0081] When the start switch 28 is pressed, the signal of the P0.1 pin of the control chip A30 changes from high level to low level, and the P1.0 pin of the control chip A30 sends a high level signal to the coil of the relay A31 for 2 seconds. The coil of the relay A31 is energized, the normally open contact of the relay A31 is closed, and the normally closed contact is opened.

[0082] The closing of the first normally open contact of relay A31 keeps the coil of relay A31 energized, the normally open contact of relay A31 remains closed, and the normally closed contact remains open. The closing of the second normally open contact of relay A31 starts the vacuum pump A9 to evacuate the space in the vacuum tank 1. The closing of the third normally open contact of relay A31 charges capacitor 34. The closing of the fourth normally open contact of relay A31 energizes the coil of electromagnetic valve E10, and the electromagnetic valve is turned on. The vacuum pump A9 is a first-stage vacuum pump, which evacuates the atmospheric pressure in the vacuum tank 1 to 1×10 -3 Pa, the voltage output by the second auxiliary power supply 27 corresponds to the pressure gauge 11 detecting 1×10 -3 Pa, so when the vacuum pump A9 pumps the air pressure in the vacuum tank 1 to below 1×10 -3 When the pressure gauge 11 outputs an analog voltage signal lower than the second auxiliary power supply 27, the output terminal of the comparator A26 outputs a high level signal in two directions:

[0083] The first direction is transmitted to the coil of relay B37. The coil of relay B37 is energized to disconnect the normally closed contact of relay B37. After the normally closed contact of relay B37 is disconnected, the coil of relay A31 loses power, the normally open contact and the normally closed contact of relay A31 return to their positions, the vacuum pump A9 stops working, and the solenoid valve E10 is closed.

[0084] The second direction is transmitted to the coil of relay C35, and the coil of relay C35 is energized, so that the first normally open contact of relay C35 is closed to keep the coil of relay C35 energized, the normally open contact of relay C35 is kept closed, and the normally closed contact is kept open. The third normally open contact of relay C35 is closed to continue charging capacitor 34, and the second and fourth normally open contacts of relay C35 are closed to connect the power supply of vacuum pump B3 and energize the coil of solenoid valve F2, so that vacuum pump B3 starts to continue to evacuate the inside of vacuum tank 1 until the vacuum reaches 1×10 -6 Pa, the voltage output by the third auxiliary power supply 39 corresponds to the pressure gauge 11 detecting 1×10 -6 Pa, so when the vacuum pump B3 pumps the air pressure in the vacuum tank 1 to below 1×10 -6 When the pressure gauge 11 outputs an analog voltage signal lower than the third auxiliary power supply 39, the output terminal of the comparator B38 outputs a high level signal in two directions:

[0085] The first direction sends a high level signal to the coil of relay E43 through port A;

[0086] The coil of the second direction relay D36 sends a high-level signal, the coil of relay D36 is energized, the normally closed contact of relay D36 is disconnected, the coil of relay C35 is de-energized, the normally open contact and the normally closed contact of relay C35 return to their positions, the vacuum pump B3 stops evacuating, the solenoid valve F2 is closed, and the vacuum in the vacuum tank 1 is maintained.

[0087] When comparator B38 sends a signal to relay D36, it also sends a signal to the coil of relay E43 through port A. The coil of relay E43 is energized, so that the normally open contact of relay E43 is closed, and solenoid valve A5 is energized and turned on. The gas in the space to be detected is drawn into the vacuum tank 1 through the gas flow channel 6. During the drawing process, the gas is mixed and reacted with the liquid droplets in the three liquid storage bins and then sprayed into the vacuum tank 1. It collides upward and rebounds downward to form liquid at the bottom of the vacuum tank 1. After the solenoid valve A5 is turned on, the gas pressure in the vacuum tank 1 will rise rapidly. Comparator B38 stops sending signals due to the increase in the voltage of the analog signal sent by the barometer. After the signal at port A disappears, port B continues to supply power to keep the coil of relay E43 energized. The normally open contact of relay E43 is closed, and solenoid valve A5 can be continuously opened to allow the vacuum tank 1 to continue to draw gas.

[0088] The coil of relay D36 is energized, causing the coil of relay C35 to lose power. The third normally open contact of relay C35 returns to its position. At this time, capacitor 34 stops charging and starts to discharge in reverse. Power is provided through port B. The discharge characteristic of capacitor 34 is utilized here. As the discharge occurs, the discharge voltage of capacitor 34 will gradually decrease. The voltage of the fourth auxiliary power supply 45 is equal to the minimum operating voltage of the coil of relay A31. Capacitor 34 continues to discharge to ensure that the coil of relay E43 is energized, the normally open contact is closed, and the solenoid valve A5 can be opened. When the discharge voltage is lower than the fourth auxiliary power supply 45, the signal output end of comparator C44 sends a signal. At the same time, the voltage is too low, and the coil of relay E43 cannot remain closed. Then the normally open contact returns to its position, the solenoid valve A5 is closed, and the vacuum tank 1 stops inhaling air and is also full of air.

[0089] Comparator C44 sends a signal to the P0.2 pin of control chip A30 through port C. After the P0.2 pin of control chip A30 receives the signal, it times 10 seconds to allow the three liquid storage tanks and hydrogen chloride gas to react fully. Then it controls the P1.1 and P1.2 pins to send high-level signals through port D and port E respectively. Port E sends the signal to the coil of relay F42, so that the coil of relay F42 is energized, and the normally open contact of relay F42 is closed. The first normally open contact of relay F42 is closed to keep the coil of relay F42 energized, and the normally open contact of relay F42 is kept closed. The coils of solenoid valve B7, solenoid valve C8 and solenoid valve D40 are energized and turned on at the same time. Solenoid valve B7 is turned on, and the accumulated liquid flows out of the vacuum tank 1. Solenoid valve C8 and solenoid valve D40 are turned on, so that nitrogen enters the vacuum tank 1 for purging, so that the upper space and the lower space of the blocking cover 4 are purged, and the vacuum tank 1 is cleaned to ensure the accuracy of the next detection. At the same time, it is used as a power to blow the liquid that has reacted and turned color out of the vacuum tank 1. After purging for 10 seconds, the P1.3 pin of the control chip sends a 2s control signal to the coil of the relay G41 through port F, and the coil of the relay G41 is energized, and the normally closed contact of the relay G41 is disconnected, so that the coil of the relay F42 is de-energized, and the normally open contact of the relay F42 returns to its position, and the solenoid valve B7, the solenoid valve C8 and the solenoid valve D40 are closed, that is, the purging of the vacuum tank 1 stops, and the liquid is discharged, and it is ready for the next vacuuming. At the same time, the P1.0 pin of the control chip A30 sends a high-level signal for 2s again, so that the next vacuuming-inhalation-liquid discharge process starts, forming a cycle.

[0090] After port D sends a signal to the P0.1 pin of the control chip B46 for the first time, the P1.0 pin of the control chip B46 sends a high-level signal, the control relay H47 coil is energized, the normally open contact of the relay H47 is closed, and the solenoid valve Ga17 is turned on, so that the pipeline leads to the first material bin of the spectrophotometer material box 12, and the liquid in the vacuum tank 1 is blown out into the first material bin of the spectrophotometer material box 12. The high-level signal sent by the P1.0 pin lasts for 2s. After 2s, the P1.0 pin stops sending the high-level signal, and the P1.1 pin sends a high-level signal of 8s to the coil of the relay I48. The normally open contact of the relay I48 is closed, the solenoid valve Gb18 is turned on, and the remaining waste liquid is discharged, and one round of detection is completed.

[0091] After entering the second detection, port D sends a signal to the P0.1 pin of the control chip B46 for the second time, and now it is necessary to discharge liquid to the second material bin of the spectrophotometer material box 12. The P1.2 pin of the control chip B46 sends a high-level signal, the control relay J49 and relay K51 coils are energized, the normally open contacts of relay J49 and relay K51 are closed, the solenoid valve Gc16 and the solenoid valve Ha15 are turned on, so that the pipeline leads to the second material bin of the spectrophotometer material box 12, and the liquid in the vacuum tank 1 is blown out into the second material bin of the spectrophotometer material box 12. The high-level signal sent by the P1.2 pin lasts for 2s. After 2s, the high-level signal sent by the P1.2 pin stops, and the P1.3 pin sends a high-level signal of 8s to the gate electrode of the relay L50 and the thyristor 53. The thyristor 53 is connected in parallel at both ends of the normally open contact of the relay J49, and the gate electrode is connected to the P1.3 pin. The gate electrode is turned on by the high-level signal, the solenoid valve Hb14 and the solenoid valve Gc16 are turned on, and the remaining waste liquid is discharged, and the second round of detection is completed. And so on, until reaching the last round of detection preset in the control chip B46, it returns to the first detection.

[0092] The following is a further description of the method for detecting hydrogen chloride concentration in conjunction with the embodiments of the present application:

[0093] The method for detecting the concentration of hydrogen chloride,

[0094] Step 1: Evacuate the vacuum tank 1; use a two-stage vacuum pump to pump the atmospheric pressure in the vacuum tank 1 to 1×10 - 6 Pa, the vacuum tank 1 can be evacuated more quickly by using two-stage vacuum pumps for different vacuum degrees.

[0095] Step 2: Open the valve and use the negative pressure in the vacuum tank 1 to spray the gas and reaction liquid in the detection environment into the vacuum tank 1 in the form of water mist;

[0096] When the gas is inhaled through the atomizing device 25, sodium hydroxide, mercuric thiocyanate solution dissolved in anhydrous ethanol and ammonium ferric sulfate dissolved in perchloric acid are inhaled into the exhaust tank 1 in sequence to react and develop color.

[0097] The reaction formula of hydrogen chloride gas and color developing solution in the contraction part 24 is:

[0098] 2Cl - +Hg(SCN)2→HgCl2+2SCN - ,

[0099] SCN - +Fe 3+ →Fe(SCN) 2+ (orange-red);

[0100] Step 3: After the water mist settles and reacts to develop color, the color-developing liquid is blown into the material box 12 of the spectrophotometer using the positive pressure formed by nitrogen purge;

[0101] Step 4: Detect by spectrophotometer to obtain the concentration of hydrogen chloride.

[0102] In the method for detecting the concentration of hydrogen chloride, the color-developing liquid blown out by the vacuum tank 1 each time enters different material slots 13 of the spectrophotometer material box 12. After each material slot 13 is full, the material box 12 is directly replaced, and the full material box 12 is loaded into the spectrophotometer to form a concentration change curve.

Claims

1. A hydrogen chloride concentration detection device, comprising a vacuum tank (1), characterized in that: The vacuum tank (1) is connected to a vacuum pump, and two-stage vacuum pumps are provided, namely, vacuum pump A (9) and vacuum pump B (3). The vacuum pumping range of vacuum pump A (9) is 1 -1 ×10 -3 Pa, the vacuum range of vacuum pump B (3) is 1×10 -3 -1×10 -6 Pa, the bottom of the vacuum tank (1) is connected to an atomizing device (25) through an air inlet pipe, a blocking cover (4) is provided inside the vacuum tank (1), mist entering the vacuum tank (1) through the atomizing device (25) is sprayed toward the blocking cover (4), a nitrogen purge pipe is connected inside the vacuum tank (1), a liquid discharge pipe is provided at the bottom of the vacuum tank (1), and the liquid discharge pipe is connected to a material box (12) of a spectrophotometer; The atomizing device (25) comprises a gas flow passage (6) and a liquid storage tank, the liquid storage tank being connected to the gas flow passage (6), the gas flow passage (6) comprising an air intake portion (22), a contraction portion (24) and a spray portion (19), the through cross section of the contraction portion (24) being one quarter of the air intake portion (22), the spray portion (19) being an open funnel-shaped structure and having a scattering device disposed therein, so that the formed water mist is rapidly dispersed and enters the vacuum tank (1), the contraction portion (24) contracts the cross section to increase the flow rate, and the high-speed flowing gas draws out the liquid in the liquid storage tank and atomizes it; the air intake portion (22) is connected to the environment to be detected via an electromagnetic valve A (5), and the other end is connected to the contraction portion (24); The liquid storage tank is connected to the side wall of the contraction part (24); the HCl in the drawn-in gas reacts with the color-developing liquid in the liquid storage tank to develop color and perform subsequent detection, and the reaction liquid is sequentially drawn out when the gas passes through, and reacts sequentially. Although the speed is very fast, after the collision into tiny droplets, the reaction area is very large and the reaction speed is also very fast, so the water mist can develop color after being sprayed into the suction tank (1); the other end of the contraction part (24) is connected to the spray part (19); The spray portion (19) extends into the vacuum tank (1) and sprays toward the blocking cover (4). The blocking cover (4) is suspended on the top of the vacuum tank (1) by a connecting rod. The blocking cover (4) is in the shape of an inverted arc structure. In order to make the sprayed water mist turn down and return to the bottom of the arc cover to avoid unimpeded spread to various places in the vacuum tank (1), the gas and the droplets collide with the blocking cover (4), and another uniform collision occurs, which helps the gas and the droplets to react.

2. The hydrogen chloride concentration detection device according to claim 1, characterized in that: The vacuum tank (1) is connected to two vacuum pumps, namely vacuum pump A (9) and vacuum pump B (3). The vacuum pump A (9) and vacuum pump B (3) are connected to the vacuum tank (1) via solenoid valve E (10) and solenoid valve F (2) respectively, and are also connected to a pressure gauge (11).

3. The hydrogen chloride concentration detection device according to claim 1, characterized in that: There are three liquid storage bins, two of which are arranged on both sides of the gas flow channel (6), and the liquid storage bins on both sides are cross-connected to the gas flow channel (6).

4. The hydrogen chloride concentration detection device according to claim 2, characterized in that: Two nitrogen purge pipes are provided in the vacuum tank (1), one of which extends from the bottom of the vacuum tank (1) into the vacuum tank (1) and blows toward the bottom surface of the blocking cover (4), and the other enters from the top of the vacuum tank (1) and blows toward the top surface of the blocking cover (4). The two purge pipes are respectively provided with a solenoid valve C (8) and a solenoid valve D (40).

5. The hydrogen chloride concentration detection device according to claim 4, characterized in that: The discharge pipe includes a main discharge pipe, a branch discharge pipe and a cleaning pipe. The discharge pipe is provided with a solenoid valve group. The solenoid valves in the solenoid valve group are respectively installed on the branch discharge pipe and the cleaning pipe and between the adjacent branch discharge pipes corresponding to the main discharge pipe.

6. The hydrogen chloride concentration detection device according to claim 5, characterized in that: A solenoid valve B (7) is provided at the connection between the main discharge pipe and the liquid storage bin.

7. The hydrogen chloride concentration detection device according to claim 6, characterized in that: A control device is provided, which receives a signal from a pressure gauge (11) and controls the operation of a vacuum pump A (9), a vacuum pump B (3), a solenoid valve A (5), a solenoid valve B (7), a solenoid valve C (8), a solenoid valve D (40), a solenoid valve E (10), a solenoid valve F (2) and a solenoid valve group.

8. A method for detecting hydrogen chloride using the hydrogen chloride concentration detection device according to any one of claims 1 to 7, characterized in that: Step 1: Evacuate the vacuum tank (1); Step 2: Open the valve and utilize the negative pressure in the vacuum tank (1) to spray the gas and reaction liquid in the detection environment into the vacuum tank (1) in the form of water mist; Step 3: After the water mist settles and reacts to develop color, the color-developing liquid is blown into the material box (12) of the spectrophotometer using the positive pressure formed by nitrogen purge; Step 4: Detect by spectrophotometer to obtain the concentration of hydrogen chloride.

9. The method for detecting hydrogen chloride according to claim 8, characterized in that: The color-developing liquid blown out of the vacuum tank (1) each time enters different material slots (13) of the spectrophotometer material box (12). After each material slot (13) is filled, the material box (12) is directly replaced, and the filled material box (12) is loaded into the spectrophotometer to form a concentration change curve.

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