An automatic calibration device for an SCD sulfur chemiluminescence detector

Abstract

The utility model discloses an automatic calibration device of SCD sulfur chemiluminescence detector. The combustion chamber of detector has first ceramic pipe, connects chromatographic column export, oxygen pipeline and tail blow pipeline, and the inside of first ceramic pipe is equipped with second ceramic pipe and hydrogen pipeline. The automatic calibration device contains sulfide standard gas steel bottle, pressure control valve, six -way sampling valve, desulfurization trap and current -limiting device, and six -way sampling valve is equipped with six interfaces, and tail blow gas inlet is connected with tail blow pipeline, and tail blow gas outlet is connected with first ceramic pipe, and quantitative gas inlet is connected with sulfide standard gas steel bottle through pressure control valve, and quantitative gas outlet is connected with standard gas sample import through quantitative ring, and standard gas sample import is connected with standard gas sample export, and standard gas sample export is connected with desulfurization trap through current -limiting device. The device can improve the detection sensitivity and accuracy, realizes automatic calibration, and is suitable for trace sulfide detection.

Description

Technical Field

[0001] This utility model relates to sulfide detection, specifically to an automatic calibration device for an SCD chemiluminescence detector. Background Technology

[0002] Sulfur oxides released from the combustion of fuels such as gasoline, diesel, and liquefied petroleum gas have been identified as key culprits in inducing acid rain and exacerbating smog. Consequently, countries have set strict limits on the sulfur content in petroleum products and emissions, driving sulfur detection technology toward higher sensitivity and stronger anti-interference capabilities.

[0003] However, sulfur in ambient air and water often exists in trace or even ultra-trace amounts. Traditional detection equipment generally suffers from insufficient selectivity and susceptibility to interference from hydrocarbon matrices, making it difficult to achieve accurate characterization of trace sulfur. With increasingly stringent environmental standards, the shortcomings of existing equipment in detecting complex samples, such as narrow linear range and poor response stability, are becoming increasingly prominent. There is an urgent need for a sulfur chemiluminescence detection technology that combines high sensitivity, a wide linear range, and strong resistance to matrix interference to meet the stringent requirements of trace sulfur monitoring.

[0004] As a crucial element in ensuring detection accuracy, the performance of the calibration device directly impacts the reliability of the sulfur chemiluminescence detector. Traditional calibration methods rely on manual operation, which is not only cumbersome and inefficient but also prone to poor repeatability due to human error, making it difficult to meet the high-precision requirements of trace sulfur detection. Therefore, developing an efficient and accurate automatic calibration device is of great significance for improving the practicality of sulfur chemiluminescence detectors and the reliability of detection data. Utility Model Content

[0005] This utility model provides an automatic calibration device for an SCD sulfur chemiluminescence detector. The SCD sulfur chemiluminescence detector is equipped with a sample redox combustion chamber. A first ceramic tube is provided in the sample redox combustion chamber. One end of the first ceramic tube is internally connected to a chromatographic column outlet, an oxygen supply line, and a tail blow line. A second ceramic tube is provided inside the other end of the first ceramic tube. One end of the second ceramic tube is connected to a hydrogen line, and the other end is open and connected to the inside of the first ceramic tube. The length of the second ceramic tube is shorter than that of the first ceramic tube. A gap is left between the second ceramic tube and the first ceramic tube, and this gap is connected to a reaction chamber. The reaction chamber is connected to an ozone generator. The automatic calibration device is characterized by including a sulfide standard gas cylinder, a pressure reducing control valve, a six-way injection valve, a desulfurization trap, and a flow limiting device.

[0006] The six-way injection valve has six ports: tail gas inlet, tail gas outlet, metering gas inlet, metering gas outlet, standard gas sample inlet, and standard gas sample outlet.

[0007] The tail gas inlet is connected to the tail gas outlet, the tail gas inlet is connected to the tail gas pipeline, and the tail gas outlet is connected to the first ceramic tube.

[0008] The metered gas inlet is connected to the metered gas outlet. The metered gas inlet is connected to the sulfide standard gas cylinder via a pressure reducing control valve, and the metered gas outlet is connected to the standard gas sample inlet via a metering loop.

[0009] The standard gas sample inlet is connected to the standard gas sample outlet, and the standard gas sample outlet is connected to the desulfurization trap through a flow limiting device.

[0010] Furthermore, the sample oxidation-reduction combustion chamber is equipped with an oxidation zone combustion chamber and a reduction zone combustion chamber connected in series. The oxidation zone combustion chamber and the reduction zone combustion chamber are respectively equipped with a heating device and a temperature sensor. The internal temperature of the oxidation zone combustion chamber is higher than that of the reduction zone combustion chamber. The first ceramic tube passes through the oxidation zone combustion chamber and the reduction zone combustion chamber in sequence.

[0011] Furthermore, one end of the second ceramic tube is located inside the first ceramic tube within the combustion chamber of the reduction zone.

[0012] Furthermore, the reaction chamber is equipped with photomultiplier tubes and filters.

[0013] Furthermore, the oxygen supply pipeline is connected to the first ceramic tube and the ozone generator respectively via a tee, and a pressure regulating valve is installed between the tee and the ozone generator;

[0014] One end of the ozone generator is connected to the oxygen supply pipeline, and the other end is connected to the reaction chamber.

[0015] Furthermore, the preheating device is a heating base installed in the sample oxidation-reduction combustion chamber near the oxidation zone combustion chamber, and the capillary column at the outlet of the chromatographic column passes through the heating base and is connected to the inside of the first ceramic tube.

[0016] Furthermore, the volume of the sulfide standard gas cylinder is 2L.

[0017] Furthermore, it also includes a calibration controller, which is connected to a pressure reducing control valve, a six-way injection valve, a desulfurization trap, and an SCD sulfur chemiluminescence detector.

[0018] The automatic calibration device for the SCD sulfur chemiluminescence detector provided by this utility model has the following advantages:

[0019] 1. Enables automated calibration: Equipped with a calibration controller, it is connected to a pressure reducing control valve, a six-way injection valve, a desulfurization trap, and an SCD sulfur chemiluminescence detector, which can automatically complete the calibration process without manual operation, reducing human error and improving calibration efficiency.

[0020] 2. Ensuring Calibration Accuracy: A quantitative loop is used for standard gas metering, precisely controlling the amount of standard gas entering the detection system and ensuring calibration accuracy and repeatability. Furthermore, the instrument automatically performs a three-needle calibration, judging the results by the repeatability pass value. If within the acceptable range, the correction factor ratio is adjusted to ensure the reliability of the calibration results; if the deviation is too large, a maintenance prompt is triggered, facilitating timely troubleshooting and ensuring the accuracy of subsequent instrument tests.

[0021] 3. Reduced Interference: Equipped with a desulfurization trap, it can capture sulfides flowing out of the standard sample, preventing sulfides in the standard gas from interfering with the surrounding environment and other testing processes. The flow limiting device can regulate the flow rate, ensuring that the standard gas enters the relevant components at a stable flow rate, guaranteeing the stability of the calibration process and reducing interference caused by flow fluctuations.

[0022] 4. Good adaptability: This automatic calibration device can be effectively combined with the SCD sulfur chemiluminescence detector, realizing automatic calibration without damaging the original structure and function of the detector, thus improving the practicality of the entire detection system. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A simplified structural diagram of a sulfur chemiluminescence detector;

[0025] Figure 2 Flowchart of sulfur chemiluminescence detector analysis;

[0026] Figure 3 This is a schematic diagram of an automatic calibration device. Detailed Implementation

[0027] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid confusion with the present invention.

[0028] To fully understand this utility model, detailed steps and structures will be presented in the following description to illustrate the technical solution of this utility model. Preferred embodiments of this utility model are described in detail below; however, in addition to these detailed descriptions, this utility model may have other embodiments.

[0029] Reference Figure 1-3 As shown, this utility model provides an automatic calibration device 100 for an SCD sulfur chemiluminescence detector. The SCD sulfur chemiluminescence detector and the automatic calibration device 100 are described below.

[0030] SCD sulfur chemiluminescence detector

[0031] like Figure 1-2 As shown, the SCD sulfur chemiluminescence detector includes a sample oxidation-reduction combustion chamber 1, a first ceramic tube 2, a second ceramic tube 5, a reaction chamber 7, and an ozone generator 9.

[0032] The sample oxidation-reduction combustion chamber 1 is equipped with an oxidation zone combustion chamber 11 and a reduction zone combustion chamber 12 connected in series. The oxidation zone combustion chamber 11 and the reduction zone combustion chamber 12 are respectively equipped with heating devices to provide heating temperature for oxidation-reduction. The internal temperature of the oxidation zone combustion chamber 11 is higher than the internal temperature of the reduction zone combustion chamber 12.

[0033] The first ceramic tube 2 is located in the sample oxidation-reduction combustion chamber 1 and passes through the oxidation zone combustion chamber 11 and the reduction zone combustion chamber 12 in sequence. One end of the first ceramic tube 2 is internally connected to the chromatographic column outlet 3 and the oxygen supply line 4. The chromatographic column outlet 3 and the oxygen supply line 4 are used to introduce sulfur-containing gas and oxygen into the first ceramic tube 2, respectively.

[0034] One end of the second ceramic tube 5 is located inside the first ceramic tube 2 in the combustion chamber 12 of the reduction zone. The other end of the second ceramic tube 5 is connected to a hydrogen pipeline 6, which is used to introduce hydrogen into the first ceramic tube 2. The outer diameter of the second ceramic tube 5 is smaller than the inner diameter of the first ceramic tube 2 to form a gap channel between the first ceramic tube 2 and the second ceramic tube 5.

[0035] One end of the reaction chamber 7 is connected to the slit channel at the other end of the first ceramic tube 2, and the other end of the reaction chamber 7 is connected to the vacuum system 8. The reaction chamber 7 is equipped with a chemiluminescence zone, which includes a photomultiplier tube and a filter. The final step of the sample reaction is carried out in this position.

[0036] One end of the ozone generator 9 is connected to the oxygen supply pipeline 4, and the other end is connected to the reaction chamber 7. The ozone generator 9 is used to generate ozone and deliver it to the reaction chamber 7.

[0037] In an optional embodiment, the oxygen supply line 4 is connected to the first ceramic tube 2 and the ozone generator 9 via a tee 41, and a pressure regulating valve 42 is provided between the tee 41 and the ozone generator 9.

[0038] In an optional embodiment, the present invention further includes a tailpipe 10, which is internally connected to one end of the first ceramic tube 2.

[0039] In an optional embodiment, a preheating device 13 is also included. The preheating device 13 is a heating base installed in the sample redox combustion chamber 1 near the oxidation zone combustion chamber 11, which preheats the gas entering the combustion chamber and connects the capillary column to the sample redox combustion chamber 1.

[0040] In an optional embodiment, the oxygen supply line 4, the hydrogen supply line 6, and the tailpipe line 10 are all equipped with electronic flow control valves.

[0041] In an optional embodiment, the vacuum system 8 includes a vacuum pump and an ozone destruction trap. The vacuum pump is used to evacuate the detector system to a negative pressure state, and the ozone destruction trap is used to decompose ozone into oxygen.

[0042] In an optional embodiment, temperature sensors are provided in both the oxidation zone combustion chamber 11 and the reduction zone combustion chamber 12 to determine the heating temperature of the oxidation zone combustion chamber 11 and the reduction zone combustion chamber 12, respectively.

[0043] In an optional embodiment, the system further includes a circuit control system, a signal acquisition system, and a vacuum detection system. The temperature sensor, electronic flow control valve, vacuum system 8, ozone generator 9, and pressure regulating valve are all connected to the circuit control system. The signal acquisition system is used to record detector signal values. The vacuum detection system is used to read the vacuum level of the piping system. The circuit control system, signal acquisition system, and vacuum detection system are existing technologies and will not be described in detail here.

[0044] The implementation steps of this utility model are as follows:

[0045] 1) The sample flows through the chromatographic column to the heating base, and then enters the large ceramic tube (i.e., the first ceramic tube 2) through the nozzle.

[0046] 2) The existing preheating zone (i.e., oxidation zone combustion chamber 11) remains unchanged, but a lower heating device is added. The lower heating device of oxidation zone combustion chamber 11 can reach a maximum temperature of 1200℃. The lower heating device is responsible for oxidation and is set at 920-950℃. Oxygen or air flows from the heating base into the lower heating device. In this way, the lower device meets both the conditions of high temperature and oxygen enrichment, which can ensure the complete oxidation of the sample. When sulfur-containing compounds pass through the bottom, they are first oxidized into sulfur-containing oxides at high temperature.

[0047] 3) The upper heating device of the combustion chamber 12 in the reduction zone is set at 700-800℃, and excess hydrogen gas is introduced above the upper heating device, flowing out from below through the small ceramic tube (i.e., the second ceramic tube 5). At this time, the upper heating device meets the conditions of high temperature and hydrogen richness, which can ensure the complete reduction of the sample. When the oxidized sulfur oxides are carried to the upper part by the pump, they are reduced to SO in the hydrogen-rich high-temperature environment. Then, they reach the reaction chamber 7 through the transmission line and undergo a chemiluminescent reaction with excess ozone. The spectrum is captured by the multiplier, thus obtaining the response.

[0048] Automatic calibration device 100

[0049] like Figure 2-3 As shown, the automatic calibration device 100 includes a 2L sulfide standard gas cylinder 110, a pressure reducing control valve 120, a six-way injection valve 140, a desulfurization trap 150, a flow limiting device 160, and a calibration controller (not shown in the figure).

[0050] As shown in the figure, the six-way injection valve 140 has ports 1 to 6 in a counterclockwise direction. These ports 1 to 6 are respectively tail gas inlet 143, tail gas outlet 142, metering gas inlet 145, metering gas outlet 144, standard gas sample inlet 141, and standard gas sample outlet 146.

[0051] 1) The tail gas inlet 143 is connected to the tail gas outlet 142, and the tail gas inlet 143 is connected to the tail gas pipeline 10, and the tail gas outlet 142 is connected to the first ceramic tube 2. The nitrogen gas transported by the tail gas pipeline 10 enters the sample oxidation-reduction combustion chamber 1 of the SCD sulfur chemiluminescence detector through the tail gas inlet 143 and the tail gas outlet 142.

[0052] 2) The metered gas inlet 145 and the metered gas outlet 144 are connected. The metered gas inlet 145 is connected to the sulfide standard gas cylinder 110 through the pressure reducing control valve 120. The metered gas outlet 144 is connected to the standard gas sample inlet 141 through the metering ring 147. The size of the metering ring 147 is set according to the sample on site.

[0053] 3) The standard gas sample inlet 141 is connected to the standard gas sample outlet 146. A flow limiting device 160 with adjustable flow rate is connected to the outlet pipe of the standard gas sample outlet 146 to limit the flow. A desulfurization trap 150 is connected to the end of the outlet to trap the sulfides flowing out of the standard sample.

[0054] The calibration controller is connected to the pressure reducing control valve 120, the six-way injection valve 140, the desulfurization trap 150, and the SCD sulfur chemiluminescence detector. The calibration controller performs automatic calibration through a calibration program. It should be noted that the calibration program is a conventional technique used by those skilled in the art and will not be described in detail here.

[0055] This invention adds an automatic calibration device 100 to the side of the SCD sulfur chemiluminescence detector. The automatic calibration device 100 includes a 2L sulfide standard gas cylinder and is equipped with a pressure reducing valve. A pressure reducing valve is connected in series with a switching valve to form a pressure reducing control valve 120, which is controlled by the testing system.

[0056] When calibration of the SCD sulfide chemiluminescence detector is required, the system automatically initiates the calibration process: First, the calibration controller issues a command to open the pressure reducing control valve 120. The sulfide standard gas in the sulfide standard gas cylinder 110, after being depressurized, enters the pipeline, purging the metering loop 147 and related connecting pipelines for 30 seconds. This purging process removes residual air, impurities, or residual gas from previous calibrations from the pipeline, preventing interference with the purity and quantitative accuracy of the current standard gas and ensuring a stable and reliable concentration of standard gas entering the detection system.

[0057] After a 30-second purging process, the six-way injection valve 140 switches to the injection state. At this time, the tail gas nitrogen delivered by the tail gas pipeline serves as the carrier gas, smoothly pushing the standard gas sample in the quantitative loop 147 into the sample oxidation-reduction combustion chamber 1 of the SCD sulfur chemiluminescence detector. The standard gas is fully oxidized to sulfur-containing oxides in the oxidation zone combustion chamber (high-temperature oxygen-rich environment), and then enters the reduction zone combustion chamber (high-temperature hydrogen-rich environment) to be reduced to SO. Finally, it undergoes a chemiluminescence reaction with the ozone delivered by the ozone generator in the reaction chamber. The light signal generated by the reaction is captured by the photomultiplier tube and converted into an electrical signal, forming the detector's output signal.

[0058] The testing system acquires the output signal in real time and, based on its built-in sulfide correction factor database (containing the proportions of response coefficients for different types of sulfides), uses the sulfide response value of the standard gas as a benchmark to proportionally correct the calibration factors for other sulfides in the database. For example, if the response value of hydrogen sulfide in the standard gas deviates from the theoretical value, the system will simultaneously adjust the calibration factors for other sulfides such as methanethiol and diethyl sulfide to ensure the consistency of detection results for various sulfides, thereby achieving accurate recalibration of the detector.

[0059] To further ensure the reliability of calibration results, the instrument automatically performs a three-needle continuous calibration procedure: repeating the above calibration operation three times under the same conditions, recording the response value of the standard gas each time. The system presets a repeatability threshold. If all three results are within the acceptable range, it indicates that the instrument is stable, and the system will automatically update the correction factor ratio and save the calibration results. If the deviation of the three results exceeds the acceptable threshold, it indicates that the instrument may have problems such as pipeline leakage, insufficient purity of the standard gas, or abnormal heating device. The system will immediately trigger a maintenance prompt (such as a screen pop-up or audible and visual alarm), clearly prompting the user to check and maintain the instrument, such as checking the pressure of the standard gas cylinder, aging the detector, and replacing the first and / or second ceramic tubes. After the fault is eliminated, the calibration is re-performed to ensure that the detector is always in an accurate and reliable working state.

[0060] The preferred embodiments of this utility model have been described above. It should be understood that this utility model is not limited to the specific embodiments described above. Devices and structures not described in detail herein should be understood as being implemented in a conventional manner within the art. Any person skilled in the art can make many possible variations and modifications to the technical solutions of this utility model using the disclosed methods and techniques, or modify them into equivalent embodiments with equivalent changes, without departing from the scope of the technical solution of this utility model. This does not affect the essential content of this utility model. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this utility model, without departing from the content of the technical solution of this utility model, still fall within the protection scope of the technical solution of this utility model.

Claims

1. An automatic calibration device for an SCD sulfur chemiluminescence detector, wherein the SCD sulfur chemiluminescence detector is provided with a sample redox combustion chamber, a first ceramic tube is provided in the sample redox combustion chamber, one end of the first ceramic tube is internally connected to a chromatographic column outlet, an oxygen supply line and a tail gas line, and the other end of the first ceramic tube is internally provided with a second ceramic tube, one end of the second ceramic tube is connected to a hydrogen line, the other end is open and connected to the interior of the first ceramic tube, the length of the second ceramic tube is shorter than that of the first ceramic tube, a gap is left between the second ceramic tube and the first ceramic tube and the gap is connected to a reaction chamber, and the reaction chamber is connected to an ozone generator, characterized in that... The automatic calibration device includes a sulfide standard gas cylinder, a pressure reducing control valve, a six-way injection valve, a desulfurization trap, and a flow limiting device; The six-way injection valve has six ports: tail gas inlet, tail gas outlet, metering gas inlet, metering gas outlet, standard gas sample inlet, and standard gas sample outlet. The tail gas inlet is connected to the tail gas outlet, the tail gas inlet is connected to the tail gas pipeline, and the tail gas outlet is connected to the first ceramic tube. The metered gas inlet is connected to the metered gas outlet. The metered gas inlet is connected to the sulfide standard gas cylinder via a pressure reducing control valve, and the metered gas outlet is connected to the standard gas sample inlet via a metering loop. The standard gas sample inlet is connected to the standard gas sample outlet, and the standard gas sample outlet is connected to the desulfurization trap through a flow limiting device.

2. The automatic calibration device for an SCD sulfur chemiluminescence detector as described in claim 1, characterized in that, The sample oxidation-reduction combustion chamber is equipped with an oxidation zone combustion chamber and a reduction zone combustion chamber connected in series. The oxidation zone combustion chamber and the reduction zone combustion chamber are respectively equipped with heating devices and temperature sensors. The internal temperature of the oxidation zone combustion chamber is higher than that of the reduction zone combustion chamber. The first ceramic tube passes through the oxidation zone combustion chamber and the reduction zone combustion chamber in sequence.

3. The automatic calibration device for an SCD sulfur chemiluminescence detector as described in claim 2, characterized in that, One end of the second ceramic tube is located inside the first ceramic tube in the combustion chamber of the reduction zone.

4. The automatic calibration device for an SCD sulfur chemiluminescence detector as described in claim 1, characterized in that, The reaction chamber is equipped with photomultiplier tubes and filters.

5. The automatic calibration device for an SCD sulfur chemiluminescence detector as described in claim 1, characterized in that, The oxygen supply pipeline is connected to the first ceramic tube and the ozone generator via a tee, and a pressure regulating valve is installed between the tee and the ozone generator. One end of the ozone generator is connected to the oxygen supply pipeline, and the other end is connected to the reaction chamber.

6. The automatic calibration device for an SCD sulfur chemiluminescence detector as described in claim 1, characterized in that, It also includes a preheating device, which is a heating base installed in the sample oxidation-reduction combustion chamber near the oxidation zone combustion chamber, and the capillary column at the outlet of the chromatographic column passes through the heating base and is connected to the inside of the first ceramic tube.

7. The automatic calibration device for an SCD sulfur chemiluminescence detector as described in claim 1, characterized in that, The volume of the sulfide standard gas cylinder is 2L.

8. The automatic calibration device for an SCD sulfur chemiluminescence detector as described in claim 1, characterized in that, It also includes a calibration controller, which is connected to a pressure reducing control valve, a six-way injection valve, a desulfurization trap, and an SCD sulfur chemiluminescence detector.

Images