Online sampling and separating system for gas-solid mixture of fluidizing chlorination furnace

Abstract

The invention relates to the technical field of online sampling, in particular to an online sampling and separating system for a gas-solid mixture of a fluidizing chlorination furnace. The system comprises a positionable sampling probe unit, a dynamic pressure compensation transmission unit, a multi-stage separation and analysis unit and an integrated control system. In-furnace multi-dimensional accurate sampling is achieved through the locatable sampling probe, the influence of pressure gradient on sampling representativeness is overcome in combination with a dynamic pressure compensation technology, and flow stability is ensured; complete separation and quantitative recovery of the gas phase, the solid phase and the liquid phase are completed through a multi-stage separation and trapping system; under intelligent coordination and safety interlocking protection of an integrated control system, full-process automatic closed operation is realized, the industrial problem that representative samples are difficult to obtain in high-temperature, high-pressure and toxic environments is thoroughly solved, and direct and reliable data support and technical guarantee are provided for optimizing chlorination process parameters and improving reaction efficiency and safety.

Description

Technical Field

[0001] This invention relates to the field of online sampling technology, specifically to an online sampling and separation system for gas-solid mixtures in a fluidized bed chlorination furnace. Background Technology

[0002] The fluidized bed chlorination process is the mainstream technology for producing titanium tetrachloride. It uses chlorine gas as the fluid and chlorinating agent, allowing a mixture of titanium feedstock and petroleum coke to undergo a chlorination reaction in a high-temperature (approximately 900-1000℃) fluidized bed. This process offers advantages such as high efficiency and ease of continuous production. The process route represented by "high-temperature carbonization-low-temperature chlorination" of high-titanium blast furnace slag aims to selectively chlorinate and carbide titanium while suppressing the chlorination of impurities such as calcium and magnesium by controlling the reaction temperature, representing a promising technological direction for industrialization.

[0003] However, the interior of a fluidized bed chlorination furnace is an extreme environment characterized by high temperature, pressure (positive pressure), confinement, and the presence of toxic gases such as titanium tetrachloride and chlorine. This characteristic makes it extremely difficult and even dangerous to obtain material samples from different locations within the furnace in real time and in situ during the reaction. Current production practices and existing technologies mainly suffer from the following limitations: The sampling location is fixed and singular: For example, the "Online Sampling Device and Method for High-Temperature Furnace Bed of a Large-Scale Fluidized Bed Chlorination Furnace" disclosed in authorization announcement number CN114878246B has a fixed sampling port corresponding to the boiling section, which can only obtain solid bed samples at a fixed height in the furnace bed. It is impossible to obtain gas-solid mixtures at different axial heights and radial positions in the furnace, and therefore cannot reveal the complete spatial distribution gradient of concentration, temperature and reaction process in the reactor.

[0004] Lack of adaptability to intra-furnace pressure gradients: A significant pressure gradient exists from bottom to top in a fluidized bed chlorination furnace. Current technology has not addressed how to maintain stable sampling flow rates at different locations under this gradient. Simply using a fixed negative pressure suction method may lead to over-sampling or even safety accidents in high-pressure areas, while insufficient sampling or no samples may be obtained in low-pressure areas, resulting in severely distorted samples that lose representativeness and comparability.

[0005] Due to the aforementioned technical bottlenecks, the industry has long lacked means to accurately diagnose the multi-dimensional reaction states inside fluidized bed chlorination furnaces. Therefore, there is an urgent need to develop a system and method capable of safely, online, and in-situ acquiring representative gas-solid mixtures from different locations within a fluidized bed chlorination furnace, and effectively separating and comprehensively analyzing them. This will overcome the aforementioned challenges and provide key technical support for the precise optimization of processes and equipment. Summary of the Invention

[0006] In view of this, to address the problem that existing chlorination furnaces are closed, positive pressure reaction systems containing titanium tetrachloride and toxic chlorine gases, making it difficult to obtain materials at different locations within the furnace during the reaction and to conduct subsequent analysis and testing to provide scientific guidance for process and equipment optimization, an online sampling and separation system for gas-solid mixtures in fluidized bed chlorination furnaces is provided.

[0007] This invention proposes an online sampling and separation system for gas-solid mixtures in a fluidized bed chlorination furnace, comprising: a positionable sampling probe unit, a dynamic pressure-compensated transmission unit, a multi-stage separation and analysis unit, and an integrated control system. The positionable sampling probe unit is installed on the fluidized bed chlorination furnace and can extend its sampling tip into different axial and / or radial positions within the furnace to extract gas-solid mixtures from different reaction zones. The inlet of the dynamic pressure-compensated transmission unit is connected to the outlet of the positionable sampling probe unit, configured to receive the gas-solid mixture and establish and maintain a stable suction flow rate to transport the mixture under a positive pressure gradient environment within the furnace. The inlet of the multi-stage separation and analysis unit is connected to the outlet of the dynamic pressure-compensated transmission unit, configured to sequentially perform solid-solid separation, gas-solid separation, and gas phase component separation and collection on the transported gas-solid mixture to obtain solid samples, condensed liquid samples, and quantify residual gas components, respectively. The integrated control system is connected to the positioning sampling probe unit, the dynamic pressure compensation transmission unit, and the multi-stage separation and analysis unit, respectively. It is used to coordinate the positioning of the positioning sampling probe unit, the suction and delivery of the dynamic pressure compensation transmission unit, and the separation process of the multi-stage separation and analysis unit, and to implement safety interlock protection.

[0008] In some embodiments, the positionable sampling probe unit includes a fixed sleeve and a sampling inner tube. The fixed sleeve is configured to be sealed to the wall of the fluidized bed chlorination furnace. The sampling inner tube is movably disposed inside the fixed sleeve, and its front end integrates a Venturi suction nozzle that protrudes from the fixed sleeve. The sampling inner tube is configured to be capable of axial extension and / or radial deflection within the fixed sleeve.

[0009] In some embodiments, the online sampling and separation system for gas-solid mixture in a fluidized bed chlorination furnace further includes a drive mechanism and a dynamic sealing structure. The drive mechanism is connected to the sampling inner tube and is used to drive the sampling inner tube to perform axial extension and / or radial deflection movements. The dynamic sealing structure is disposed between the fixed sleeve and the sampling inner tube.

[0010] In some embodiments, the inner wall of the throat of the Venturi suction nozzle is constructed with a spiral guide structure, and the spiral angle of the spiral guide structure is 20°~30°.

[0011] In some embodiments, the locatable sampling probe unit further includes an integrated sensing module, which is located adjacent to the suction port of the venturi nozzle. The integrated sensing module includes at least a pressure sensor and a temperature sensor disposed at the front end of the sampling inner tube.

[0012] In some embodiments, the dynamic pressure compensation transmission unit includes a vacuum ejector as a suction power source. The integrated control system is configured to dynamically adjust the operating power of the vacuum ejector based on a preset compensation algorithm using a real-time pressure signal fed back from a pressure sensor.

[0013] In some embodiments, the preset compensation algorithm is: P 引射 =k×P position +C, Among them, P 引射 The operating power of the vacuum ejector is expressed in kW (P). position The pressure value at the sampling point is determined based on the real-time pressure signal, where k is a coefficient between 0.10 and 0.14 in kPa, and C is a constant between 1.0 and 2.0.

[0014] In some embodiments, the dynamic pressure compensation transmission unit further includes a pulse backflush line. The pulse backflush line is used to inject inert gas pulses into the positionable sampling probe unit and connecting pipeline. The integrated control system is further configured to control the opening and closing of the pulse backflush line according to a preset program.

[0015] In some embodiments, the online sampling and separation system for gas-solid mixture in a fluidized bed chlorination furnace further includes a cooling unit. The cooling unit is used to cool the positionable sampling probe unit. The integrated control system is also configured to: receive real-time temperature values ​​from a temperature sensor and real-time pressure values ​​from a pressure sensor; and automatically control the positionable sampling probe unit and the dynamic pressure compensation transmission unit to stop operating and trigger the cooling unit to start when the real-time temperature value exceeds a first safety threshold or the real-time pressure value exceeds a second safety threshold.

[0016] In some embodiments, the multi-stage separation and analysis unit includes a cyclone separator, a filter, a condenser, and an alkali absorption device connected in series. The inlet of the cyclone separator constitutes the inlet of the multi-stage separation and analysis unit, used to separate the first solid particles from the gas-solid mixture. The inlet of the filter is connected to the gas phase outlet of the cyclone separator, used to capture the second solid particles from the gas phase. The inlet of the condenser is connected to the gas phase outlet of the filter, used to condense titanium tetrachloride in the gas phase into a liquid state. The inlet of the alkali absorption device is connected to the exhaust port of the condenser, used to absorb and quantify chlorine gas in the residual gas.

[0017] In some embodiments, the online sampling and separation system for the gas-solid mixture of a fluidized bed chlorination furnace further includes a purging unit. The purging unit includes an inert gas source, a main purging pipeline connected to the inert gas source, and multiple purging branches branching from the main purging pipeline and respectively connected to the inlet of the locatable sampling probe unit, the inlet of the dynamic pressure compensation transmission unit, and the inlet of the multi-stage separation and analysis unit. The purging unit is signal-connected to an integrated control system, which is configured to: before system startup or after each sampling cycle, control the purging unit to purge the pipelines of the locatable sampling probe unit, the dynamic pressure compensation transmission unit, and the multi-stage separation and analysis unit with inert gas.

[0018] The beneficial effects of this invention are as follows: This invention achieves multi-dimensional and precise sampling within the furnace through a positionable sampling probe, and overcomes the influence of pressure gradient on the representativeness of the sample by combining dynamic pressure compensation technology, ensuring stable flow rate; it completes the separation and quantitative recovery of gas, solid, and liquid phases through a multi-stage separation and collection system; under the intelligent coordination and safety interlock protection of the integrated control system, it realizes fully automated and closed-loop operation, completely solving the industry problem of difficulty in obtaining representative samples under high temperature, high pressure, and toxic environments, and providing direct and reliable data support and technical guarantee for optimizing chlorination process parameters and improving reaction efficiency and safety. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, 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 the present invention. For those skilled in the art, other embodiments can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is an overall framework diagram of an online sampling and separation system for gas-solid mixture in a fluidized bed chlorination furnace, provided in one embodiment of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to specific examples and the accompanying drawings.

[0022] It should be noted that all uses of "first" and "second" in the embodiments of the present invention are for the purpose of distinguishing two entities or parameters with the same name but different names. It is clear that "first" and "second" are only for the convenience of expression and should not be construed as limiting the embodiments of the present invention. Subsequent embodiments will not explain this in detail.

[0023] This invention proposes an online sampling and separation system for gas-solid mixtures in fluidized bed chlorination furnaces, addressing the challenge of obtaining representative materials from different locations within the furnace for comprehensive analysis in closed, positive-pressure fluidized bed chlorination furnaces containing toxic gases. The system comprises: a positionable sampling probe unit, a dynamic pressure-compensated transmission unit, a multi-stage separation and analysis unit, and an integrated control system. Specifically, the positionable sampling probe unit is installed on the fluidized bed chlorination furnace and can extend its sampling tip into different axial and / or radial positions within the furnace to extract gas-solid mixtures from different reaction zones. The inlet of the dynamic pressure-compensated transmission unit is connected to the outlet of the positionable sampling probe unit, configured to receive the gas-solid mixture and establish and maintain a stable suction flow rate to transport the mixture under a positive pressure gradient environment within the furnace. The inlet of the multi-stage separation and analysis unit is connected to the outlet of the dynamic pressure-compensated transmission unit, configured to sequentially perform solid-solid separation, gas-solid separation, and gas phase component separation and collection on the transported gas-solid mixture to obtain solid samples, condensed liquid samples, and quantify residual gas components. The integrated control system is connected to the positioning sampling probe unit, the dynamic pressure compensation transmission unit, and the multi-stage separation and analysis unit, respectively. It is used to coordinate the positioning of the positioning sampling probe unit, the suction and delivery of the dynamic pressure compensation transmission unit, and the separation process of the multi-stage separation and analysis unit, and to implement safety interlock protection.

[0024] This invention achieves multi-dimensional and precise sampling within the furnace through a positionable sampling probe, and overcomes the influence of pressure gradient on sample representativeness by combining dynamic pressure compensation technology, ensuring stable flow. A multi-stage separation and capture system completes the separation and quantitative recovery of the gas, solid, and liquid phases. Under the intelligent coordination of the integrated control system, fully automated closed-loop operation is achieved, solving the industry problem of obtaining representative samples under high temperature, high pressure, and toxic environments. This provides direct and reliable data support and technical assurance for optimizing chlorination process parameters and improving reaction efficiency and safety.

[0025] In some embodiments, the positionable sampling probe unit specifically includes a fixed sleeve and a sampling inner tube. The fixed sleeve is a hollow tube made of a high-temperature resistant alloy (such as Hastelloy C276) with a flange at one end. It is connected to a pre-installed interface flange on the wall of the fluidized bed chlorination furnace via the flange, with a high-temperature resistant sealing gasket sandwiched in between to achieve a high-pressure static seal with the furnace body. The sampling inner tube is also made of a high-temperature resistant alloy and is coaxially nested inside the fixed sleeve. The front end of the sampling inner tube is machined into a streamlined or flat-head shape, and a venturi suction nozzle is opened and fixed (e.g., welded) or integrally formed on the side wall near the front end. The suction port of the venturi suction nozzle protrudes from the fixed sleeve to reach into the furnace environment. The rear end of the sampling inner tube is connected to an external drive mechanism. The drive mechanism may include a linear actuator for driving the sampling inner tube to extend and retract along the axis of the fixed sleeve. Its extension / retraction stroke can cover a depth range of, for example, 0.2 meters to 5.0 meters. The linear actuator may be, for example, a screw drive mechanism consisting of a servo motor and a ball screw pair, a hydraulic drive mechanism, an electric push rod, a telescopic mechanism, etc.; and / or, the drive mechanism may include a rotary actuator for driving the sampling inner tube to rotate to different radial positions. The rotary actuator may include a first rotary mechanism rotating about a horizontal axis, with the rear end of the sampling inner tube connected to the first rotary mechanism. The first rotary mechanism can rotate the sampling inner tube about the horizontal axis at different tilt angles to different radial positions. The rotary actuator may also include a second rotary mechanism rotating about a vertical axis, connected between the linear actuator and the first rotary mechanism. The second rotary mechanism can rotate the tilted sampling inner tube about the vertical axis at different angles to different circumferential positions. The first and second rotary mechanisms may include drive motors, and the rotation angle of the sampling inner tube is controlled by controlling the drive motors. Thus, by controlling the drive mechanism, precise positioning of the sampling end in the three-dimensional space inside the furnace can be achieved. To achieve absolute sealing of the furnace pressure during the movement of the sampling inner tube, a multi-stage combined dynamic sealing structure is installed in the annular gap between the fixed sleeve and the sampling inner tube. This structure typically includes a combination of multiple sealing stages, such as a high-temperature flexible graphite packing seal near the furnace interior and a metal bellows mechanical seal near the outer side, ensuring no leakage under high-temperature and pressurized conditions. Through this structural design, the probe unit in this embodiment can overcome the limitations of traditional fixed-point sampling, safely and in-situ acquiring gas-solid mixture samples at any specified axial height and radial position within the furnace, accurately reflecting the reaction state of the reactor's internal spatial distribution.

[0026] In some embodiments, the inner wall of the throat of the venturi nozzle is constructed with a spiral guide structure, the spiral angle of which is 20°~30°, preferably 25°. The function of this spiral guide structure is to forcibly impart a tangential velocity component when the gas-solid mixture is drawn through the throat, thereby forming a vortex. The centrifugal force generated by this vortex helps to throw heavier solid particles towards the outer edge of the tube wall, preventing them from settling and accumulating in the low-velocity zone at the center of the throat, effectively preventing throat blockage. Simultaneously, the vortex promotes vigorous agitation and mixing between the gas and solid particles, resulting in a more homogeneous sample.

[0027] In some embodiments, the positionable sampling probe unit further includes an integrated sensing module, which includes at least a pressure sensor and a temperature sensor. These sensors are directly encapsulated or embedded in the front end of the sampling inner tube, adjacent to the suction port of the Venturi suction nozzle, but located to its side or rear to avoid direct high-speed scouring by the material. By setting up pressure and temperature sensors, the absolute pressure and material temperature parameters at the sampling point can be acquired synchronously in real time and in situ.

[0028] In some embodiments, the dynamic pressure compensation transmission unit includes a vacuum ejector as a suction power source. The vacuum ejector utilizes the strong entrainment effect generated by a high-pressure working medium (such as compressed nitrogen) to actively extract the high-temperature gas-solid mixture from the reaction zone at the inlet of the sampling inner tube. It has excellent high pressure differential adaptability and can be steplessly adjusted from 0 to 200 kPa. The integrated control system is configured to dynamically adjust the operating power of the vacuum ejector based on the real-time pressure signal fed back by the pressure sensor, using a preset compensation algorithm. Specifically, the preset compensation algorithm is as follows: P 引射 =k×P position +C, Among them, P 引射 P represents the operating power of the vacuum ejector, measured in kW. position The sampling point pressure value is determined based on the real-time pressure signal, in kPa; k is a coefficient between 0.10 and 0.14; and C is a constant between 1.0 and 2.0. The dynamic pressure compensation algorithm in this embodiment accurately maps the real-time pressure signal inside the furnace to the required power of the vacuum ejector through a linear relationship. It can intelligently offset the influence of the positive pressure gradient inside the furnace caused by changes in sampling point depth on the suction power, enabling the system to automatically maintain a constant volumetric suction flow rate when sampling in different pressure zones. This ensures that the samples taken from the high-pressure zone to the low-pressure zone have high consistency and comparability in terms of gas-solid ratio and flow rate time reference, fundamentally solving the sampling distortion problem caused by pressure fluctuations in traditional methods.

[0029] In some embodiments, the dynamic pressure compensation transmission unit further includes a pulse backflush line. The pulse backflush line is used to inject inert gas pulses into the locatable sampling probe unit and connecting pipeline. Specifically, the pulse backflush line includes a high-pressure inert gas source, a pulse solenoid valve group controlled by the integrated control system, a pressure regulator, and directional spray ports distributed behind the throat of the venturi suction nozzle and at easily blocked points in the transmission pipeline. The integrated control system is further configured to control the opening and closing of the pulse backflush line according to a preset program. Specifically, the integrated control system is configured to execute two control modes: one is a periodic pulse based on a fixed time interval (e.g., triggered once every 30-90 seconds), and the other is to automatically trigger diagnostic enhanced backflush when an abnormal decrease in the inlet negative pressure or flow rate of the vacuum ejector is detected. During each backflush, the system controls the solenoid valve to open for a very short time (e.g., 0.05-0.15 seconds), injecting a high-pressure (e.g., 0.2-0.5 MPa) inert gas (usually nitrogen) into the pipeline in the form of a transient shock wave. This invention utilizes the instantaneous high-speed shear force and pressure oscillation generated by pulsed airflow to forcibly remove the fine particle adhesion layer and nascent scale deposited on the inner wall of the sampling system. This effectively avoids the risk of continuous reduction in pipeline flow area, decreased suction efficiency, or even complete blockage caused by material accumulation, thereby ensuring that the system can maintain stable and reliable continuous sampling capability under harsh conditions of long-term operation and high dust load.

[0030] In some embodiments, the fixed sleeve is internally provided with a cooling channel, and the online sampling and separation system for gas-solid mixture in a fluidized bed chlorination furnace also includes a cooling unit for cooling the positionable sampling probe unit. The cooling unit specifically includes a compressed nitrogen source, a vortex tube cooler, or a circulating water cooling system. The compressed nitrogen, after being cooled by the vortex tube, generates a low-temperature airflow (or circulating cooling water), which is introduced into the jacketed cooling channel of the fixed sleeve to provide enveloping forced convection cooling to the sampling inner tube. The integrated control system is further configured to: receive real-time temperature signals from a temperature sensor; and automatically control the positionable sampling probe unit and the dynamic pressure compensation transmission unit to stop working and trigger the cooling unit to open when the real-time temperature value exceeds a first safety threshold (e.g., 180~220°C) or the real-time pressure value exceeds a second safety threshold (e.g., 1.1~1.3 times the furnace working pressure) when the real-time temperature value exceeds a first safety threshold (e.g., 180~220°C) or the real-time pressure value exceeds a second safety threshold (e.g., 1.1~1.3 times the furnace working pressure). Specifically, the integrated control system first cuts off the power to the vacuum ejector and stops the insertion of the sampling inner tube; then it closes the main shut-off valve of the sampling pipeline to achieve physical isolation; simultaneously, it increases the power of the cooling unit to the maximum and cuts in emergency purging nitrogen into the pipeline. This embodiment, through active temperature control and multiple safety interlocks, ensures the structural integrity and thermal stability of the positionable sampling probe unit during long-term operation in the extreme high temperature (up to 1000℃) environment inside the furnace, preventing material failure, seal damage, or sensor damage due to overheating; and in case of abnormal operating conditions, it can automatically, quickly, and safely interrupt the sampling process and implement protection, fundamentally eliminating the serious safety risks of toxic gas leakage or fire and explosion caused by equipment failure.

[0031] In some embodiments, the multi-stage separation and analysis unit includes a cyclone separator, a filter, a condenser, and an alkali absorption device connected in series. The inlet of the cyclone separator constitutes the inlet of the multi-stage separation and analysis unit, used to separate the first solid particles from the gas-solid mixture. Specifically, a tangential inlet cyclone separator (tangential flow velocity 15~25 m / s) can achieve efficient primary separation of coarse particles larger than 10~20 μm (such as unreacted carbonized slag) with its high centrifugal force field. The inlet of the filter is connected to the gas phase outlet of the cyclone separator, used to capture the second solid particles from the gas phase. Specifically, the filter can be a sintered metal cartridge filter (precision 3~8 μm), which is also equipped with a pulse backflushing device. The pulse backflushing device operates at a gas pressure of 0.3~0.5 MPa at intervals of 10~60 s, which can deeply purify the dust-laden gas, capture volatile impurities such as chlorides and other ultrafine dust, and avoid clogging. The condenser inlet is connected to the gas phase outlet of the filter to condense titanium tetrachloride in the gas phase into a liquid state. Specifically, the condenser is a coil-type cryogenic condenser, which uses -5℃ to -10℃ chilled brine as a refrigerant to fully condense and liquefy titanium tetrachloride vapor. The pipes are placed at an angle to guide the condensed titanium tetrachloride into a titanium tetrachloride collection bottle. The inlet of the alkali absorption device is connected to the exhaust port of the condenser. It contains a quantitative and known concentration of NaOH solution to absorb and quantify chlorine in the residual gas. The amount of chlorine absorbed is accurately calculated by monitoring changes in pH or the increase in chloride ions. This multi-stage series purification process achieves complete phase separation and component capture of high-temperature complex gas-solid mixtures. It can not only obtain solid samples with different particle sizes and physicochemical properties in stages, but also simultaneously recover high-purity titanium tetrachloride liquid and accurately quantify unreacted chlorine, thus providing comprehensive key process data such as reaction conversion rate, chlorine utilization rate, product purity, and impurity distribution in one go.

[0032] In some embodiments, the online sampling and separation system for the gas-solid mixture of a fluidized bed chlorination furnace further includes a purging unit. The purging unit includes an inert gas source, a main purging pipeline connected to the inert gas source, and multiple purging branches branching from the main purging pipeline and connected to the inlet of the locatable sampling probe unit, the inlet of the dynamic pressure compensation transmission unit, and the inlet of the multi-stage separation and analysis unit, respectively. The inert gas source is a high-pressure nitrogen cylinder or the plant's nitrogen pipeline network. The main purging pipeline and the purging branches are equipped with solenoid valves controlled by an integrated control system. The solenoid valves of the purging unit are signal-connected to the integrated control system, which is configured to open the solenoid valves of the purging unit before system startup or after each sampling cycle, introducing inert gas into the pipelines of the locatable sampling probe unit, the dynamic pressure compensation transmission unit, and the multi-stage separation and analysis unit for purging. Furthermore, the integrated control system is configured to set the purging pressure of the inert gas to be at least 20% higher than the predetermined pressure at the target sampling point when controlling the purging unit to execute the purging procedure. By performing a purging process before system startup, accumulated air, moisture, or residual corrosive materials from the previous sampling are thoroughly removed from the pipeline, providing a clean and inert initial environment for sampling. This fundamentally avoids sample contamination and safety risks caused by the violent reaction of TiCl4 with water. Performing a purging process after each sampling cycle forces out any residual materials (especially hygroscopic or corrosive chloride powder) that may adhere to or deposit in the pipeline, effectively preventing pipeline corrosion, blockage, and the resulting sampling distortion and decreased system reliability.

[0033] The system operation method provided by this invention, based on the aforementioned architecture of four parts working in tandem—a positionable sampling probe unit, a dynamic pressure compensation transmission unit, a multi-stage separation and analysis unit, and an integrated control system—achieves fully automated operation from precise in-furnace sampling to complete sample analysis. Its core process can be divided into the following five stages: Phase 1: System Initialization and Preparation The operator starts the system via the human-machine interface, and the integrated control system first executes the purging procedure. Its control purging unit opens the solenoid valve of the corresponding branch, introducing high-purity nitrogen from the high-pressure nitrogen cylinder or pipeline network at a pressure more than 20% higher than the predetermined sampling point pressure (e.g., 0.3~0.5MPa) into the pipelines of the positionable sampling probe unit, the dynamic pressure compensation transmission unit, and the multi-stage separation and analysis unit, respectively. The purging continues for at least 5 minutes to thoroughly remove air, moisture, and any residual materials from the pipelines, establishing a clean and inert initial environment.

[0034] Simultaneously, the integrated control system activates the cooling unit, introducing compressed nitrogen (e.g., 0.5~0.8MPa) into the cooling channel of the fixed sleeve, thereby reducing the temperature at the front end of the sampling inner tube to below 150℃, a safe operating range, through the vortex tube effect. The system also synchronously calibrates the pressure and temperature sensors integrated at the probe's front end.

[0035] Phase Two: Target Localization and Dynamic Compensation Sampling The operator sets the axial depth and radial angle coordinates of the target sampling point on the control interface. The integrated control system drives the linear and rotary actuators to extend and / or deflect the sampling inner tube within the fixed sleeve, precisely moving the integrated venturi suction nozzle to the designated position inside the furnace.

[0036] The integrated control system reads the signal P from the pressure sensor at this position in real time. position And based on the preset compensation algorithm P 引射 =k×P position +C (where k is 0.10~0.14 and C is 1.0~2.0), automatically calculates and sets the operating power of the vacuum ejector to accurately offset the influence of the furnace pressure on the suction flow rate at that point.

[0037] The system sequentially opens the sampling pipeline valves and starts the vacuum ejector with the set power to begin suction at a constant target flow rate (e.g., 5~15 L / min). The gas-solid mixture enters the system through a Venturi suction nozzle with a spiral guide structure at the throat. Simultaneously, to prevent pipeline blockage, the integrated control system triggers pulse backflushing of the pipeline at preset intervals (e.g., 30~90 seconds), injecting high-pressure short-duration nitrogen pulses (e.g., 0.4 MPa, 0.1 seconds).

[0038] Throughout the sampling process, the integrated control system continuously monitors temperature and pressure signals. If the temperature exceeds the first safety threshold (e.g., 180~220℃) or the pressure is abnormal, the system will immediately interrupt this stage and jump to the fifth stage (safety emergency response).

[0039] Phase 3: Multi-stage separation and quantitative recovery of components After sampling is completed at the predetermined time, the gas-solid mixture is transported to a multi-stage separation and analysis unit for four-stage processing: The mixture first enters the cyclone separator at the tangential inlet. Under the action of a high centrifugal force field, most of the coarse solid particles with a particle size larger than its cutting particle size (e.g., >20μm) are separated and collected as the first solid sample in the first sample container.

[0040] The gas exiting the cyclone separator carries fine powder into a metal filter cartridge (with an accuracy of 3~8μm). The fine particles are captured by the filter cartridge and shaken off into a second sample container by periodic pulse backflushing (e.g., 0.3~0.5MPa), serving as a second solid sample.

[0041] The gas, after solid particles have been removed, enters the condenser. The condenser is maintained at a low temperature (e.g., -10°C to -5°C) through a refrigerant circulation system, causing the titanium tetrachloride vapor in the gas phase to condense into a liquid state, which then flows into a dedicated titanium tetrachloride collection bottle.

[0042] The remaining tail gas (mainly containing unreacted chlorine) enters the alkaline absorption device. A measured amount of alkaline solution (e.g., 10% NaOH) absorbs the chlorine. By analyzing the changes in the composition of the alkaline solution before and after absorption (e.g., pH value, chloride ion concentration), the chlorine consumption or residual amount at that sampling point can be accurately calculated.

[0043] Phase 4: System Reset and Loop Preparation After a complete sampling-separation cycle is completed: The integrated control system closes the sampling valve and stops the vacuum ejector.

[0044] The system automatically executes the purging procedure again to remove any residual material in the pipeline, preparing for the next sampling.

[0045] The operator can set new sampling point coordinates, and the system repeats stages two through four to achieve continuous analysis at different locations. Solid samples taken multiple times can be mixed to improve representativeness.

[0046] Phase 5: Safety Emergency Response This is a continuous safety procedure. Once the integrated control system detects that the temperature or pressure at the probe tip exceeds the safety threshold, it will instantly trigger the following interlocking actions: Emergency shutdown: Immediately stop all movement of the vacuum ejector and probe.

[0047] Pipeline isolation: Close the critical shut-off valves of the sampling pipeline.

[0048] Enhanced cooling and emergency purging: Adjust the cooling power of the cooling unit to the maximum and start the high-pressure emergency purging of the entire pipeline until the system parameters return to normal.

[0049] Through the above-mentioned highly integrated, automated, and intelligent five-stage workflow, this system enables safe, in-situ, and representative online sampling at any designated location inside the boiling chlorination furnace under high temperature, positive pressure, and toxic conditions, while simultaneously completing the complete separation and precise quantification of the gas, solid, and liquid phases.

[0050] The present invention will be further illustrated below with reference to the embodiments. The embodiments are only used to illustrate the present invention and are not intended to limit the invention in any way.

[0051] Example 1: Sampling at a distance of 1.0 meter from the gas distribution plate inside the furnace This embodiment demonstrates the process and results of online sampling and separation at a distance of 1.0 meter from the gas distribution plate inside the furnace (measured pressure 60 kPa, temperature 495 °C).

[0052] First, the purging program is initiated via the integrated control system, purging the locatable sampling probe unit, dynamic pressure compensation transmission unit, and connecting pipelines for 5 minutes at a pressure of 0.4 MPa using high-purity nitrogen. Simultaneously, the cooling unit is activated, introducing 0.5 MPa compressed nitrogen into the cooling channel of the fixed sleeve for vortex tube cooling, reducing the temperature at the front end of the sampling inner tube to 142°C. The pressure and temperature sensors in the integrated sensing module are then calibrated.

[0053] Position the front end of the sampling inner tube to the target depth. The integrated control system reads the real-time pressure value of 60 kPa, and calculates the pressure based on the compensation algorithm P. 引射 =0.12×60+1.5 The automatic setting of the vacuum ejector operating power is 8.7kW, and it is controlled to start suction at a constant flow rate of 5L / min. During the 4-minute sampling process, the system automatically triggers the pulse backflush pipeline every 60 seconds, injecting a nitrogen pulse with a pressure of 0.4MPa and a duration of 0.1 seconds.

[0054] The obtained gas-solid mixture enters a multi-stage separation and analysis unit. Coarse solid particles are separated in a cyclone separator. The gas passes through a 5μm pore size metal filter, while fine powder is retained and collected via 0.4MPa nitrogen backflushing. The gas phase enters a condenser maintained at -8°C, where titanium tetrachloride vapor is condensed. The residual gas is passed into an alkaline absorption device containing a 10% NaOH solution.

[0055] Results: In this embodiment, a total solid sample of 432 grams was obtained, 98 grams of liquid titanium tetrachloride were collected, and the amount of absorbed chlorine gas was calculated to be 9.34 grams through alkaline analysis.

[0056] Example 2: Sampling was taken 2.5 meters from the gas distribution plate inside the furnace. The example demonstrates the sampling process at a higher position inside the furnace (2.5 meters from the distribution plate, measured pressure 42 kPa, temperature 560°C), focusing on the parameter adaptation under different pressures and temperatures.

[0057] The purging pressure was 0.3 MPa for 5 minutes. The cooling nitrogen pressure was increased to 0.8 MPa to stabilize the probe tip temperature at 136°C.

[0058] The integrated control system calculated and set the vacuum ejector power to 6.54 kW based on a real-time pressure of 42 kPa. The suction flow rate was set to a relatively high 15 L / min. Due to the high temperature at this location, to prevent clogging, the pulse backflush interval was shortened to once every 30 seconds (pressure 0.4 MPa, duration 0.1 seconds), with a total sampling time of 1 minute.

[0059] The separation unit operates in the same manner as in Example 1, except that the backflush pressure of the metal filter element is 0.2 MPa and the condensation temperature is -5°C.

[0060] Results: 68 g of solid sample and 16.4 g of liquid titanium tetrachloride were obtained, and the calculated amount of chlorine gas was 1.26 g. The data indicate that the reactant concentration at this location differs from that at the lower part.

[0061] Example 3: Sampling at a distance of 4.5 meters from the gas distribution plate inside the furnace. This embodiment demonstrates long-term sampling at a sampling point near the upper part of the furnace body (4.5 meters from the distribution plate, pressure 18 kPa, temperature 520°C) to accumulate sufficient sample.

[0062] The purging pressure is 0.5 MPa. The cooling nitrogen pressure is 0.6 MPa, and the probe tip temperature is 143℃.

[0063] The integrated control system automatically sets the vacuum ejector power to a lower setting of 3.66 kW based on the low pressure of 18 kPa. The suction flow rate is 7 L / min. Due to the low pressure and potentially low material density, the pulse backflush interval is extended to once every 90 seconds. To obtain sufficient samples, the total sampling time is extended to 9 minutes.

[0064] During the operation of the separation unit, the backflushing pressure of the metal filter element is 0.2 MPa, and the condensation temperature is reduced to -10℃ to ensure condensation efficiency.

[0065] Results: A large amount of solid sample (1108 g) and liquid titanium tetrachloride (56.8 g) were obtained, and the calculated chlorine content was 20.9 g. These results reflect the enrichment and reaction characteristics of the material in the upper part of the furnace.

[0066] The above three embodiments fully demonstrate the effectiveness, adaptability, and reliability of the system and method described in this invention. The system can automatically adjust key parameters such as cooling intensity, suction power, backflushing frequency, and sampling time according to the pressure and temperature at different locations within the furnace, ultimately achieving complete separation and quantitative recovery of the gas, solid, and liquid phases. The obtained multi-dimensional data is of extremely high value for mapping the reaction state within the furnace and optimizing process parameters.

[0067] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0068] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An online sampling and separation system for gas-solid mixture in a fluidized bed chlorination furnace, characterized in that, include: The positioning sampling probe unit is installed on the fluidized bed chlorination furnace and can extend its sampling tip into different axial and / or radial positions inside the furnace to extract gas-solid mixtures from different reaction zones. A dynamic pressure compensation transmission unit, which is connected to the positionable sampling probe unit, is configured to receive the gas-solid mixture and establish and maintain a stable suction flow rate to transport the gas-solid mixture under the positive pressure gradient environment in the furnace. A multi-stage separation and analysis unit, connected to the dynamic pressure-compensated transmission unit, is configured to sequentially perform solid-solid separation, gas-solid separation, and gas phase component separation and collection on the delivered gas-solid mixture to obtain solid samples, condensed liquid samples, and quantify residual gas components, respectively; and An integrated control system is connected to the positionable sampling probe unit, the dynamic pressure compensation transmission unit, and the multi-stage separation and analysis unit, respectively, to coordinate the positioning of the positionable sampling probe unit, the suction and delivery of the dynamic pressure compensation transmission unit, and the separation process of the multi-stage separation and analysis unit.

2. The system according to claim 1, characterized in that, The positionable sampling probe unit includes: A fixed sleeve is configured to be sealed to the furnace wall of the fluidized bed chlorination furnace; The sampling inner tube is movably disposed inside the fixed sleeve, and a Venturi suction nozzle is integrated thereon, which protrudes from the fixed sleeve. The sampling inner tube is configured to be able to perform axial extension and / or radial deflection within the fixed sleeve.

3. The system according to claim 2, characterized in that, Also includes: A drive mechanism, connected to the sampling inner tube, is used to drive the sampling inner tube to perform the axial extension and / or radial deflection movements; and A dynamic sealing structure is provided between the fixed sleeve and the sampling inner tube.

4. The system according to claim 2 or 3, characterized in that, The inner wall of the throat of the Venturi suction nozzle is constructed with a spiral flow guiding structure, and the spiral angle of the spiral flow guiding structure is 20°~30°.

5. The system according to claim 2 or 3, characterized in that, The positionable sampling probe unit also includes: An integrated sensing module, which is located adjacent to the suction port of the venturi nozzle, includes at least a pressure sensor and a temperature sensor disposed at the front end of the sampling inner tube.

6. The system according to claim 5, characterized in that, The dynamic pressure compensation transmission unit includes: Vacuum ejector, used as a suction power source; The integrated control system is configured as follows: Based on the real-time pressure signal fed back by the pressure sensor, the operating power of the vacuum ejector is dynamically adjusted through a preset compensation algorithm.

7. The system according to claim 6, characterized in that, The preset compensation algorithm is as follows: P 引射 =k×P position +C, Among them, P 引射 The operating power of the vacuum ejector is expressed in kW (P). position The pressure value at the sampling point is determined based on the real-time pressure signal, in kPa, where k is a coefficient between 0.10 and 0.14, and C is a constant between 1.0 and 2.

0.

8. The system according to claim 6, characterized in that, The dynamic pressure compensation transmission unit also includes: A pulse backflush line is used to inject inert gas pulses into the positionable sampling probe unit and the connecting line. The integrated control system is further configured to control the opening and closing of the pulse backflush pipeline according to a preset program.

9. The system according to claim 5, characterized in that, Also includes: A cooling unit is provided for cooling the positionable sampling probe unit. The integrated control system is further configured to: receive real-time temperature values ​​fed back by the temperature sensor and real-time pressure values ​​fed back by the pressure sensor; and when the real-time temperature value exceeds a first safety threshold or the real-time pressure value exceeds a second safety threshold, automatically control the positionable sampling probe unit and the dynamic pressure compensation transmission unit to stop working and trigger the cooling unit to start.

10. The system according to claim 1, characterized in that, The multi-level separation and analysis unit comprises units connected in series: The cyclone separator, whose inlet forms the inlet of the multi-stage separation and analysis unit, is used to separate the first solid particles from the gas-solid mixture. A filter, the inlet of which is connected to the gas phase outlet of the cyclone separator, is used to capture second solid particles from the gas phase; A condenser, the inlet of which is connected to the gas phase outlet of the filter, is used to condense titanium tetrachloride in the gas phase into a liquid state; An alkaline solution absorption device, the inlet of which is connected to the exhaust port of the condenser, is used to absorb and quantify chlorine gas in the residual gas.

11. The system according to claim 1, characterized in that, Also includes: The purging unit includes an inert gas source, a main purging pipeline connected to the inert gas source, and multiple purging branches branching from the main purging pipeline and respectively connected to the inlet of the positionable sampling probe unit, the inlet of the dynamic pressure compensation transmission unit, and the inlet of the multi-stage separation and analysis unit. The purging unit is signal-connected to the integrated control system, which is configured to purge the pipelines of the positionable sampling probe unit, the dynamic pressure compensation transmission unit, and the multi-stage separation and analysis unit with inert gas before system startup or after each sampling cycle.

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