A multi-point sampling mechanism for a high temperature sampling system
The high-temperature sampling system, with its multiple probes and electrically heated filters, solves the problems of multi-point sampling and safety, achieving stable and safe high-temperature sampling.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NANJING CENTURY ARK ANALYTICAL INSTR
- Filing Date
- 2023-03-30
- Publication Date
- 2026-05-12
AI Technical Summary
Existing high-temperature sampling systems lack multi-point sampling design, and cooling water decomposes to produce oxygen and hydrogen under ultra-high temperature conditions, posing safety hazards.
Multiple probes are used to achieve multi-point sampling, and an electrically heated post-stage filter and flow transmitter are equipped to monitor the cooling water flow. The cooling water flow and system status are adjusted in real time through a PLC control system to prevent cooling water leakage.
It achieves multi-point sampling and improved safety, avoids gas condensation and dust adsorption, prevents cooling water leakage into the furnace top, and ensures stable system operation.
Smart Images
Figure CN116337546B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of gas sampling technology, and more specifically to a multi-point sampling mechanism for a high-temperature sampling system. Background Technology
[0002] Gas sampling and analysis technology for steelmaking converters refers to continuously monitoring the composition of the gas at the top of the furnace and calculating relevant parameters during the blowing process, such as the decarburization rate and oxygen content in the gas. This allows for the determination of the carbon content, component content, molten pool temperature, and slag composition in the molten steel, as well as the adjustment of oxygen and coolant dosages to achieve control over converter smelting. Therefore, gas sampling is necessary.
[0003] Patent application number CN202020477369.2 discloses a high-temperature gas sampling and temperature measurement device for the top of a converter furnace. It describes a device comprising: a sampling probe, a ball valve, a reducing sub, a high-temperature alloy steel probe, a thermometer, and a flange seat; a flange seat is provided at the top of the converter furnace, and the flange seat is sequentially connected to the reducing sub, the ball valve, and the sampling probe; the high-temperature alloy steel probe consists of a probe body and a flange, with the flange at the top of the probe body, and the flange sandwiched between two flanges correspondingly connected to the reducing sub and the flange seat; the probe... The bottom end of the probe body extends downward into the gas phase space at the top of the converter; the upper end of the thermometer is fixedly connected to the flange, and the lower end of the thermometer extends downward into the gas phase space at the top of the converter. The device described in this utility model simultaneously possesses gas sampling and temperature measurement functions. It has a simple structure, a long probe lifespan, and the probe is easy to replace and maintain. While ensuring detection accuracy, it can operate stably for extended periods. For example, patent application number 201822233506.3 describes a device comprising "a sampling pipeline connected to a gas flow pipeline." The device includes a purging calibration line and a venting line. The sampling line is sequentially equipped with a first ball valve, a check valve, a secondary pressure reducing valve, a second ball valve, a primary filter, a first rotor flowmeter, a high-efficiency filter, and an oxygen analyzer. The inlet of the purging calibration line is connected to both the compressed air and nitrogen supply lines via a three-position three-way valve. A third ball valve is installed on the compressed air supply line, and a fourth ball valve is installed on the nitrogen supply line. A primary pressure reducing valve is also installed on the purging calibration line. The outlet of the purging calibration line is connected to the sampling line between the check valve and the secondary pressure reducing valve. The venting line is located on the sampling line between the secondary pressure reducing valve and the second ball valve, and is equipped with a venting ball valve and a second rotor flowmeter. While the above two patents can achieve the purpose of high-temperature gas sampling, they both lack a design for multi-point sampling. Furthermore, due to the ultra-high temperature environment (above 1200℃) inside the furnace top, the cooling water will decompose into oxygen and hydrogen under these conditions. The generation of oxygen could cause an explosion, resulting in poor safety and failing to meet the usage requirements.
[0004] In conclusion, developing a multi-point sampling mechanism for high-temperature sampling systems remains a critical issue that urgently needs to be addressed in the field of gas sampling technology. Summary of the Invention
[0005] To address the aforementioned shortcomings of existing technologies, this invention provides a multi-point sampling mechanism for a high-temperature sampling system. This invention achieves multi-point sampling through multiple sets of probes. The downstream filter is electrically heated to prevent condensation of gas after filtration, which would then mix with dust and adhere to the filter element, affecting the normal operation of the downstream filter. Furthermore, the flow transmitter in the cooling water path monitors the flow rate of cooling water at the sampler's inlet and outlet. When the data from the two flow transmitters differ by a certain margin, the electric ball valves at the cooling water inlet and outlet are immediately closed. The electric ball valves also send a closure signal to the control system, which shuts down the entire sampling system and sends an alarm signal. On-site maintenance personnel then investigate the fault. This effectively prevents cooling water leakage within the sampler and its flow into the furnace top, improving safety.
[0006] To achieve the above objectives, the present invention provides the following technical solution:
[0007] This invention provides a multi-point sampling mechanism for a high-temperature sampling system, comprising a sampler, a cooling backflushing control box, and a PLC control system, wherein:
[0008] There are two samplers, each of which includes a probe and a heat exchanger. The probe is installed at the front end of the heat exchanger, and the rear end of the heat exchanger is connected to a post-filter via a pipe. A first temperature sensor is installed on both the heat exchanger and the post-filter.
[0009] The cooling backflush control box is equipped with a nitrogen backflush system and a water cooling system, wherein:
[0010] The nitrogen backflushing system includes a gas storage tank. A pressure sensor and a second temperature sensor are installed on the top of the gas storage tank. Four sets of pipes are connected to the bottom of the gas storage tank. Each set of pipes is equipped with a pneumatic valve in sequence. Every two sets of pipes are connected to the rear end of the heat exchanger and the sample outlet end of the post-filter, respectively. The inlet end of the gas storage tank is connected to a first filter pressure reducing valve and a second ball valve in sequence through pipes.
[0011] The water cooling system includes a manifold solenoid valve assembly, two sets of cooling water inlet components, and a cooling water outlet component. The air inlet of the manifold solenoid valve assembly is connected in sequence to a third ball valve, a second filter pressure reducing valve, and a fourth ball valve via a pipe. Each cooling water inlet component includes a solenoid valve and a first needle valve connected in parallel. The outlet of the solenoid valve and the first needle valve is connected in sequence to a first flow transmitter and a first electric ball valve via a pipe. Each cooling water inlet component is connected to the cooling water inlet of the heat exchanger. The inlet of the solenoid valve and the first needle valve is connected to a fifth ball valve via a pipe. The cooling water outlet component includes a sixth ball valve, a second flow transmitter, and a second electric ball valve connected in series via a pipe. The cooling water outlet component is connected to the cooling water outlet of the heat exchanger. The outlet of the sixth ball valve is connected to a seventh ball valve via a pipe.
[0012] A further feature of the present invention is that the air inlet end of the third ball valve is connected to a second needle valve via a pipe.
[0013] A further feature of the present invention is that the PLC control system is installed inside the cooling backflushing control box.
[0014] A further feature of the present invention is that the first temperature sensor is connected to the PLC control system via a wire.
[0015] A further feature of the present invention is that both the pressure sensor and the second temperature sensor are connected to the PLC control system via wires.
[0016] A further configuration of the present invention is that the solenoid valve, the first flow transmitter, and the first electric ball valve are all connected to the PLC control system via wires.
[0017] A further configuration of the present invention is that the second flow transmitter and the second electric ball valve are both connected to the PLC control system via wires.
[0018] Compared with known public technologies, the technical solution provided by this invention has the following advantages:
[0019] Beneficial effects:
[0020] (1) The present invention can set up multiple samplers and achieve multi-point sampling through the set probes. When the sampler starts working, the cooling water inlet and outlet are opened and the cooling water is sent into the sampler for heat exchange. The sample outlet temperature of the sampler is monitored and the flow rate of the cooling water is adjusted according to the temperature to ensure that the gas after heat exchange in the sampler maintains the set temperature.
[0021] (2) The present invention sends the heat-exchanged gas into the downstream filter. Since the downstream filter has an electric heating function, it avoids the gas from condensing after filtration and mixing with dust, which would then be adsorbed on the filter element and affect the normal use of the downstream filter. It also extends the service life of the downstream filter.
[0022] (3) The function of the flow transmitter in the cooling water flow path of the present invention is to monitor the flow rate of cooling water at the inlet and outlet of the sampler. When the data of the two flow transmitters change beyond a certain difference, the electric ball valves at the inlet and outlet of the cooling water are immediately closed. The electric ball valves send a closing signal to the control system, which shuts down the entire sampling system and sends an alarm signal. On-site maintenance personnel go to the site to troubleshoot the fault, thereby preventing the cooling water from leaking into the sampler and flowing into the furnace top, thus improving safety. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of a multi-point sampling mechanism for a high-temperature sampling system provided by the present invention.
[0024] Figure 2 A schematic diagram of the nitrogen backflushing system and the water cooling system in a multi-point sampling mechanism for a high-temperature sampling system provided by the present invention;
[0025] Figure 3 This is a schematic diagram of two samplers in a multi-point sampling mechanism for a high-temperature sampling system provided by the present invention.
[0026] Figure 4 This is a schematic diagram of the structure of a multi-point sampling mechanism for a high-temperature sampling system provided by the present invention.
[0027] Explanation of the labels in the diagram:
[0028] 110. Probe; 120. Heat exchanger; 130. Post-filter; 140. First temperature sensor; 211. Gas tank; 212. Pressure sensor; 213. Second temperature sensor; 214. Pneumatic valve; 215. First ball valve; 216. First filter pressure reducing valve; 217. Second ball valve; 221. Manifold solenoid valve assembly; 222. Third ball valve; 223. Second needle valve; 224. Second filter pressure reducing valve; 225. Fourth ball valve; 226. Solenoid valve; 227. First needle valve; 228. First flow transmitter; 229. First electric ball valve; 230. Fifth ball valve; 231. Sixth ball valve; 232. Second flow transmitter; 233. Second electric ball valve; 234. Seventh ball valve. Detailed Implementation
[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.
[0030] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0031] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0032] Example:
[0033] Please refer to Figures 1-4 As shown, this invention provides a multi-point sampling mechanism for a high-temperature sampling system, including a sampler, a cooling backflushing control box, and a PLC control system, wherein:
[0034] There are two samplers. Both samplers include a probe 110 and a heat exchanger 120. The probe 110 is installed at the front end of the heat exchanger 120. The rear end of the heat exchanger 120 is connected to a post-filter 130 through a pipe. A first temperature sensor 140 is installed on both the heat exchanger 120 and the post-filter 130.
[0035] The cooling backflush control box is equipped with a nitrogen backflush system and a water cooling system, wherein:
[0036] The nitrogen backflushing system includes a gas storage tank 211. A pressure sensor 212 and a second temperature sensor 213 are installed on the top of the gas storage tank 211. Four sets of pipes are connected to the bottom of the gas storage tank 211. A pneumatic valve 214 and a first ball valve 215 are installed on each set of pipes in sequence. Each pair of pipes is connected to the rear end of the heat exchanger 120 and the sample outlet end of the post-filter 130, respectively. The inlet end of the gas storage tank 211 is connected to a first filter pressure reducing valve 216 and a second ball valve 217 in sequence through pipes.
[0037] The water cooling system includes a manifold solenoid valve assembly 221, two sets of cooling water inlet components and a cooling water outlet component. The air inlet of the manifold solenoid valve assembly 221 is connected in sequence to a third ball valve 222, a second filter pressure reducing valve 224 and a fourth ball valve 225 via pipes. Each cooling water inlet component includes a solenoid valve 226 and a first needle valve 227 connected in parallel. The outlets of the solenoid valve 226 and the first needle valve 227 are connected in sequence to a first flow transmitter 228 and a first electric ball valve 229 via pipes. Each cooling water inlet component is connected to the cooling water inlet of the heat exchanger 120. The inlet of the solenoid valve 226 and the first needle valve 227 is connected to a fifth ball valve 230 via pipes. The cooling water outlet component includes a sixth ball valve 231, a second flow transmitter 232 and a second electric ball valve 233 connected in series via pipes. The cooling water outlet component is connected to the cooling water outlet of the heat exchanger 120. The outlet of the sixth ball valve 231 is connected to a seventh ball valve 234 via pipes.
[0038] In this embodiment, it should be noted that, in order to ensure that the electrical components inside the cooling back-blowing control box can work normally, the cooling back-blowing control box is also equipped with a scroll cooler to ensure that the temperature inside the cooling back-blowing control box meets the operating requirements of the internal electrical components (0-40℃).
[0039] Furthermore, taking sampler #1 as an example, during power-on operation, the first temperature sensor 140 at the inlet and outlet of the cooling water on the sampler monitors the temperature change of the cooling water in real time. The first temperature sensor 140 at the sample outlet monitors the sample outlet temperature (set temperature 120℃). This temperature signal is output by the PLC control system as a 4-20mA signal to control the proportional valve at the cooling water inlet. The higher the temperature, the larger the opening of the proportional valve, and vice versa. When the sample outlet temperature is lower than the set value, the sample valve (PVO1) opens, and the sample gas flows into the downstream filter 130. The downstream filter 130 maintains the sample gas at the set temperature. The downstream filter 130 has its own thermocouple signal sent to the PLC control system. The PLC control system controls the operation of the downstream filter 130 through its internal PID program. After the system has been running for half an hour, sampler #1 switches to purging mode. The sample valve is closed, and pneumatic valve 214 (PVO3) is opened for pulse purging, purging for 10 seconds and pausing for 2 seconds, with a cycle of two minutes. After this purging is completed, pneumatic valve 214 (PVO3) is closed, and the backflush outlet valve (PV02) and pneumatic valve 214 (PVO4) of the downstream filter 130 are opened for pulse purging, purging for 10 seconds and pausing for 2 seconds, with a cycle of two minutes. After this purging is completed, the backflush outlet valve (PV02) and pneumatic valve 214 (PVO4) of the filter are closed, and the sample valve (PV01) remains closed, waiting for the working signal of sampler #1. Five minutes before sampler #1 enters purging mode, sampler #2 enters working mode, but the sample valve (PV05) remains closed. When the purging signal of sampler #1 is received, the sample valve (PV05) can be opened if the working conditions are met. The working mode of sampler #2 is the same as that of sampler #1, and the two are used alternately in a cycle.
[0040] The first flow transmitter 228(FT01), the second flow transmitter 232(FT02), the first flow transmitter 228(FT03), and the second flow transmitter 232(FT04) at the inlet and outlet of the sampler's cooling water monitor the cooling water flow rate in real time. If the difference in data between any two flow transmitters (either the first flow transmitter 228(FT01), the second flow transmitter 232(FT02), the first flow transmitter 228(FT03), or the second flow transmitter 232(FT04)) exceeds 5%, an alarm must be triggered. The first electric ball valve 229 (MV01, MV02) and the second electric ball valve 233 (MV03, MV04) of the cooling water inlet and outlet are shut off in an emergency. The first electric ball valve 229 (MV01, MV02) and the second electric ball valve 233 (MV03, MV04) send a shut-off signal to the PLC control system. The PLC control system closes all relevant valves of the entire sampling system and sends an alarm signal. On-site maintenance personnel go to the site to troubleshoot the fault. After the fault is resolved, the maintenance personnel manually reset the system, and the system restarts.
[0041] The pressure sensor 212 and the second temperature sensor 213 on the gas storage tank 211 monitor the pressure and temperature inside the gas storage tank 211 in real time, and set a warning pressure value of 2 MPa and a temperature value of 80°C. When the set values are exceeded, the gas storage tank 211 stops heating.
[0042] In this invention, the air inlet end of the third ball valve 222 is connected to the second needle valve 223 via a pipe. The PLC control system is installed in the cooling backflushing control box. The first temperature sensor 140 is connected to the PLC control system via a wire. The pressure sensor 212 and the second temperature sensor 213 are both connected to the PLC control system via wires. The solenoid valve 226, the first flow transmitter 228, and the first electric ball valve 229 are all connected to the PLC control system via wires. The second flow transmitter 232 and the second electric ball valve 233 are both connected to the PLC control system via wires.
[0043] In this embodiment, it should be noted that the PLC control system is responsible for the power supply and control of the entire system. It contains a programmable logic controller (PLC). The temperature, pressure, flow and other signals of the entire system are sent to the PLC. Through its internal program, the PLC outputs signals to control the accurate operation of each valve, ensuring that the medium passing through the sampler meets the requirements of the downstream system.
[0044] When the present invention is powered on, the sampler starts working. The first electric ball valve 229 at the cooling water inlet and outlet opens, allowing cooling water to enter the sampler for heat exchange, maintaining the set temperature of the gas after heat exchange. The cooling water inlet flow rate is adjusted according to the sample outlet temperature; the opening increases when the temperature is high and decreases or closes when the temperature is low, keeping the sample within the set temperature range. The gas then enters the downstream filter 130, which has an electric heating function to prevent condensation after filtration, which could mix with dust and adhere to the filter element, affecting the normal operation of the downstream filter 130. After running for half an hour, the sampler... Switch to purge mode and backflush the sampler's heat exchanger 120, probe 110, and post-filter 130 sequentially. First, close the sample shut-off valve and open the probe purge valve to purge the sampler's heat exchange tube and probe 110. After purging, backflush the sampler's post-filter 130. Open the post-filter 130 backflush outlet shut-off valve and the post-filter 130 purge valve to purge the post-filter 130. After purging, close the post-filter 130 backflush outlet and keep the sample shut-off valve closed. Stop the machine and wait for the next operation. In this embodiment, two samplers are provided, one in use and one on standby, operating in an alternating mode.
[0045] Taking the operation of one of the samplers as an example, the function of the first flow transmitter 228 in the cooling water flow path is to monitor the flow rate of cooling water at the inlet and outlet of the sampler. When the data difference between the two first flow transmitters 228 exceeds a certain value, the first electric ball valve 229 at the inlet and outlet of the cooling water must be shut off immediately. The first electric ball valve 229 sends a shut-off signal to the PLC control system, which then shuts down the entire sampling system and sends an alarm signal. On-site maintenance personnel then go to the site to troubleshoot the fault. The above measures prevent cooling water from leaking into the sampler and flowing into the furnace top. Because the furnace top is an ultra-high temperature environment of over 1200℃, the cooling water will decompose into oxygen and hydrogen under this environment. The generation of oxygen could cause an explosion.
[0046] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.
Claims
1. A multi-point sampling mechanism for a high-temperature sampling system, characterized in that, Includes a sampler, a cooling backflush control box, and a PLC control system, among which: Two samplers are provided. Each sampler includes a probe (110) and a heat exchanger (120). The probe (110) is installed at the front end of the heat exchanger (120). The rear end of the heat exchanger (120) is connected to a post-filter (130) through a pipe. A first temperature sensor (140) is installed on both the heat exchanger (120) and the post-filter (130). The cooling backflush control box is equipped with a nitrogen backflush system and a water cooling system, wherein: The nitrogen backflushing system includes a gas storage tank (211). A pressure sensor (212) and a second temperature sensor (213) are installed on the top of the gas storage tank (211). Four sets of pipes are connected to the bottom of the gas storage tank (211). A pneumatic valve (214) and a first ball valve (215) are installed on each set of pipes in sequence. Each pair of pipes is connected to the rear end of the heat exchanger (120) and the sample outlet end of the post-filter (130) respectively. The inlet end of the gas storage tank (211) is connected to a first filter pressure reducing valve (216) and a second ball valve (217) in sequence through pipes. The water cooling system includes a manifold solenoid valve assembly (221), two sets of cooling water inlet components, and a cooling water outlet component. The air inlet of the manifold solenoid valve assembly (221) is connected in sequence to a third ball valve (222), a second filter pressure reducing valve (224), and a fourth ball valve (225) via pipes. Each cooling water inlet component includes a solenoid valve (226) and a first needle valve (227) connected in parallel. The outlets of the solenoid valve (226) and the first needle valve (227) are connected in sequence to a first flow transmitter (228) and a first electric ball valve (225) via pipes. 9) Each cooling water inlet assembly is connected to the cooling water inlet of the heat exchanger (120). The inlet ends of the solenoid valve (226) and the first needle valve (227) are connected to the fifth ball valve (230) through pipes. The cooling water outlet assembly includes a sixth ball valve (231), a second flow transmitter (232) and a second electric ball valve (233) connected in series through pipes. The cooling water outlet assembly is connected to the cooling water outlet end of the heat exchanger (120). The outlet end of the sixth ball valve (231) is connected to the seventh ball valve (234) through pipes.
2. The multi-point sampling mechanism for a high-temperature sampling system according to claim 1, characterized in that, The air inlet of the third ball valve (222) is connected to the second needle valve (223) via a pipe.
3. The multi-point sampling mechanism for a high-temperature sampling system according to claim 1, characterized in that, The PLC control system is installed inside the cooling backflushing control box.
4. The multi-point sampling mechanism for a high-temperature sampling system according to claim 1, characterized in that, The first temperature sensor (140) is connected to the PLC control system via a wire.
5. A multi-point sampling mechanism for a high-temperature sampling system according to claim 1, characterized in that, The pressure sensor (212) and the second temperature sensor (213) are both connected to the PLC control system via wires.
6. The multi-point sampling mechanism for a high-temperature sampling system according to claim 1, characterized in that, The solenoid valve (226), the first flow transmitter (228), and the first electric ball valve (229) are all connected to the PLC control system via wires.
7. A multi-point sampling mechanism for a high-temperature sampling system according to claim 1, characterized in that, The second flow transmitter (232) and the second electric ball valve (233) are both connected to the PLC control system via wires.