Method and system for high by-product steam of hydrogen chloride graphite synthesis furnace

Abstract

This invention discloses a method and system for producing high-yield by-product steam in a hydrogen chloride graphite synthesis furnace, relating to the field of hydrogen chloride synthesis technology. By constructing a preliminary feedback mechanism, when real-time reaction parameters deviate from the preset reaction parameter range or steam system state parameters deviate from the preset steam parameter range, the invention re-optimizes the raw material feed rate and reaction zone temperature gradient until the real-time correlated parameters return to the corresponding preset range, achieving preliminary stable control of the reaction process. Furthermore, by linking the synthesis reaction with the steam generation system, preliminary recovery and utilization of reaction waste heat is achieved. A central control unit collects real-time parameters from each unit, performs multi-dimensional calculations including raw material reactivity coefficients and heat recovery efficiency, and outputs corresponding control commands based on the calculation results, constructing a highly integrated intelligent control system. This system achieves stable control of steam output pressure, effectively reduces overall system energy consumption, and ultimately produces stable, high-purity by-product steam.

Description

Technical Field

[0001] This invention relates to the field of hydrogen chloride synthesis technology, and in particular to a method and system for producing high-yield steam in a hydrogen chloride graphite synthesis furnace. Background Technology

[0002] In the chemical production processes of chlor-alkali and polyvinyl chloride, the combustion of chlorine and hydrogen to synthesize hydrogen chloride is a crucial basic reaction, releasing a significant amount of heat. Chinese patent application CN106495099A discloses a graphite-based hydrogen chloride synthesis furnace with an economizer, comprising a graphite furnace cylinder and a steam drum. A gas remixer is located at the top of the graphite furnace cylinder. From bottom to top, the gas remixer is sequentially arranged with a sealed evaporation section, an economizer section, and a cooling section. The upper and lower parts of the evaporation section's metal structure are connected in series with the steam drum via circulation pipelines. An integral furnace bottom head is located at the bottom of the graphite furnace cylinder, on which a premixed synthesis furnace lamp is installed. An integral furnace top head is located at the top of the cooling section, with a hydrogen chloride outlet on the integral furnace top head. This patent recovers the heat energy carried by the hydrogen chloride and uses it to preheat the deionized water of the by-product steam, making more efficient use of waste heat and improving thermal efficiency. Simultaneously, it further cools the hydrogen chloride, reducing the cooling load, and offers advantages such as energy saving, efficient waste heat utilization, and high thermal efficiency.

[0003] However, existing technologies still have the following problems, making it difficult to meet the production demands for high efficiency, high quality, and low energy consumption: 1. Although the existing synthesis furnace recovers medium and low temperature waste heat through economizers, it has not designed an appropriate recovery structure for the temperature gradient differences in the reaction process. Due to the single flow state of the heat exchange medium and the limited contact area with the furnace wall, the extreme heat in the high temperature reaction zone is prone to local overheating or heat escape. The heat utilization rate of the medium temperature section has a limited improvement and has not achieved step-by-step efficient recovery across the entire temperature range. 2. Existing technologies rely heavily on single steam drums for by-product steam separation. Due to the lack of coordinated control between pressure and heat recovery efficiency, steam pressure fluctuates significantly and cannot meet the medium- and high-pressure requirements for distillation and heating in chemical production. 3. The reaction temperature and pressure control and steam system parameters lack real-time linkage. When the steam demand changes, the reaction parameter adjustment lags, which exacerbates the instability of the operating conditions. In addition, the medium flow is not designed with a transition structure, which can easily cause local heat loss due to sudden changes in the flow state, further reducing the system's overall efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for producing high-yield by-product steam in a hydrogen chloride graphite synthesis furnace, which realizes efficient utilization of heat in the hydrogen chloride synthesis process, significantly improves the yield and quality of by-product steam, and thus significantly improves thermal energy utilization efficiency, thereby solving the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A method for producing high-byproduct steam in a hydrogen chloride graphite synthesis furnace, comprising the following steps: Based on the reaction characteristics and steam production requirements of the hydrogen chloride graphite synthesis furnace, hydrogen and chlorine were selected as the reaction feed gases, and the reaction feed gases were pretreated. Based on the state of the pretreated reaction feed gas, the synthesis reaction parameters are adjusted, and the correlation parameters between the reaction system and the steam system are collected. The temperature and pressure distribution of the hydrogen chloride synthesis reaction are optimized based on the correlation parameters. The heat distribution released during the synthesis reaction is determined based on the optimized temperature distribution. A heat recovery path is set in conjunction with the associated parameters. The recovered heat is obtained and crude steam is generated according to the heat recovery path. The crude steam is then subjected to steam upgrading treatment to obtain high-yield qualified by-product steam.

[0006] Furthermore, the raw material pretreatment specifically includes: Hydrogen and chlorine are introduced into a graphite purification device to remove impurities. Based on the purity test results of the reaction raw material gas, refined hydrogen and refined chlorine with purity meeting the reaction requirements are obtained. Simultaneously, refined hydrogen and refined chlorine are mixed according to the stoichiometric ratio of the synthesis reaction to form a mixed raw material gas, which is then passed into a preheating channel for preheating to obtain a pretreated reaction raw material gas.

[0007] Furthermore, the control of the synthesis reaction parameters specifically includes: Based on the stoichiometry and purity test results of the pretreated reaction raw material gas, the raw material reactivity coefficient is calculated, and the raw material feed rate is dynamically adjusted based on the raw material reactivity coefficient. Based on the adjusted raw material feed rate and combined with the furnace structure characteristics of the hydrogen chloride graphite synthesis furnace, divide the reaction zone into no less than two zones, and simultaneously control the temperature gradient of the reaction zone. Real-time correlation parameters within the hydrogen chloride graphite synthesis furnace are obtained, including real-time reaction parameters and steam system state parameters, and the stability of the reaction system and steam system is determined based on the real-time correlation parameters. When the real-time reaction parameters deviate from the preset reaction parameter range or the steam system state parameters deviate from the preset steam parameter range, the feed rate and temperature gradient of the reaction zone are re-optimized until the real-time related parameters return to the corresponding preset range.

[0008] Furthermore, the temperature and pressure distribution of the hydrogen chloride synthesis reaction is optimized, specifically including: Based on real-time reaction parameters and combined with the stoichiometric ratio of the synthesis reaction, the raw material ratio, heat transfer intensity and furnace pressure of the hydrogen chloride graphite synthesis furnace are dynamically controlled to match the temperature and pressure distribution within the preset optimization range. The molar ratio of hydrogen to chlorine is calculated based on the flow rate of the raw material gas. When the molar ratio deviates from the preset molar ratio range, the opening of the raw material gas inlet valve is adjusted in real time to correct the molar ratio back to the preset molar ratio range. Based on the temperature of each reaction zone and the furnace wall temperature, the flow rate of the heat transfer medium in each reaction zone in the heat recovery device is adjusted, and the opening of the tail gas discharge valve of the synthesis furnace is adjusted based on the furnace pressure to dynamically adjust the steam output load. Based on the raw material ratio, heat transfer intensity and furnace pressure control results, real-time temperature and pressure distribution data of hydrogen chloride synthesis reaction are obtained, and it is determined whether the real-time temperature and pressure distribution data are within the preset optimization range. When the target temperature and pressure are not within the preset optimization range, the system returns to adjust the raw material ratio, heat transfer intensity, or furnace pressure parameters until the real-time temperature and pressure distribution return to the preset optimization range, generating stable reaction heat source conditions.

[0009] Furthermore, the heat recovery path is specifically as follows: Based on the temperature gradient of the reaction zone after regulation, and combined with the real-time temperature and pressure distribution data, the flow path of the heat exchange medium is optimized to match the flow path with the temperature gradient of the reaction zone. Based on the matching results, heat recovery paths are set for each reaction zone, and transition channels are set at the connection points of each reaction zone to ensure a smooth transition of the heat exchange medium between the reaction zones.

[0010] Furthermore, the steam upgrading treatment specifically includes: The pressure, humidity, and impurity content of the crude steam are obtained, wherein the humidity data is correlated with the humidity of the steam-water mixture in the steam system state parameters; Based on the detection results, condensate and trace solid impurities in the crude steam are removed, and the heating intensity of the steam superheating section is adjusted by combining the recovered heat obtained from the heat recovery path. When the crude steam pressure is lower than the preset pressure threshold, the heating intensity of the superheated section is increased; when the pressure is higher than the preset pressure threshold, the heating intensity is reduced so that the steam quality meets the preset quality standard.

[0011] Furthermore, the process of regulating the steam output pressure includes: Based on the real-time difference between the heat exchange medium flow rate and the furnace wall temperature, and combined with the recovery characteristics of the heat recovery path, the real-time heat recovery efficiency is calculated. Based on the real-time heat recovery efficiency and the pressure detection results of the crude steam, the pressure control parameters during the steam upgrading process are dynamically adjusted.

[0012] Furthermore, the determination of whether the real-time temperature and pressure distribution data are within the preset optimization range is achieved by converting the current temperature and pressure combination into a quantitative value of the physical state of the furnace wall, specifically including the following steps: Step 1: Establish a physical state quantification model based on acoustic-thermal coupling: Establish the dynamic phase transition critical index. A computational model characterizes the boiling heat transfer physical state of the heat exchange wall under specific thermal parameters; and an acoustic emission sensor is installed on the graphite furnace wall to obtain the reference acoustic spectrum energy density function under a preset standard nucleate boiling state. ; Step 2: Obtain real-time thermal and acoustic parameters acting on the furnace wall: Real-time acquisition of the acoustic spectrum energy density function of the reaction region. Simultaneously, the current steam pressure, which serves as a control parameter, is obtained. With circulating water mass flow rate The real-time local heat flux of the reaction zone was calculated based on the feed rate of the raw materials. ; Step 3: Calculate the dynamic phase transition critical index to quantify the physical state: Use the Kern-Seaton fouling deposition model to iteratively update the thickness of the fouling thermal resistance layer on the heat exchange wall in real time. The temperature and pressure combination obtained in step two is converted into a quantitative value of the current physical state using thermodynamic and acoustic formulas. The calculation formula is: in: The real-time local heat flux of the reaction region is defined as follows: ,in The total reaction heat load is calculated based on the feed rate. This is the heat distribution coefficient for the region. This is the effective heat transfer area of ​​the reaction region; Current steam pressure With circulating water mass flow rate The theoretical critical heat flux baseline value is obtained based on the modified vertical flow channel critical heat flux correlation. For time The dynamically accumulated thickness of the fouling thermal resistance layer on the heat exchange wall is based on the Kern-Seaton fouling deposition model. Perform real-time iterative updates. For model variation parameters, For sedimentation rate, Erosion rate; The thermal conductivity of the dirt layer; This is a correction factor for the effect of dirt surface roughness on bubble nucleation density; The real-time acoustic spectrum energy density function is obtained by an acoustic emission sensor installed on the graphite furnace wall. The reference acoustic spectrum energy density function is a preset standard nuclear boiling state. The characteristic frequency range for bubble coalescence is 20 kHz to 100 kHz. These are acoustic weighting coefficients; For integration variables; Step 4: Verify the stability of the heat source conditions based on quantitative numerical values: The calculated values... As a criterion, it is confirmed whether the current temperature and pressure regulation has achieved a stable heat source state, including: when Less than the preset safety threshold If the current temperature and pressure combination determines that a dangerous physical state of film boiling has been generated on the furnace wall, and it is confirmed that a stable heat source for reaction has not been generated, then the real-time temperature and pressure distribution data is not within the preset optimization range.

[0013] Furthermore, when step four determines that a stable heat source for reaction has not been generated, an unsteady-state control strategy is triggered, specifically including executing a superheat suppression operation based on vapor pressure to correct the physical state: While maintaining a constant feed rate, the steam outlet regulating valve is opened less to achieve a preset pressure ramp-up rate. Increase the system operating pressure on the by-product steam side; Utilizing the saturation temperature caused by pressure increase Increase, decrease the superheat between the graphite wall and the cooling medium This forces the boiling condition to revert from the transition boiling zone or the film boiling initiation zone back to the nucleus boiling zone; Simultaneously, a micro-disturbance generator located outside the heat exchange channel is activated to apply a frequency similar to that of the heat exchange medium. Matching mechanical vibrations physically disrupt the air film layer formed on the heat exchange wall, until... Return to safe threshold The above confirms the conditions for restoring a stable reaction heat source.

[0014] This invention provides another technical solution: a system for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace, comprising: The raw material pretreatment unit is used to remove impurities from hydrogen and chlorine to obtain refined raw material gas that meets the purity requirements. The reaction control and temperature and pressure optimization unit is used to correct the molar ratio of hydrogen and chlorine in real time based on flow data, control the temperature gradient of each reaction zone, dynamically adjust the steam output load based on the furnace pressure, and optimize the temperature and pressure distribution of the synthesis reaction. The stepped heat recovery unit is used to design differentiated heat exchange paths to match the temperature gradient of the reaction zone, capture high heat in the high-temperature zone and residual heat in the low-temperature zone, enhance heat transfer between the furnace wall and the heat exchange medium, and achieve a smooth flow transition of the heat exchange medium. The steam upgrading unit is used to collect data on the pressure, humidity, and impurity content of crude steam, remove condensate and trace solid impurities from the crude steam, and adjust the heating intensity of the superheated section based on the recovered heat to optimize the steam pressure and purity. The steam pressure and output control unit is used to store the upgraded steam, calculate the real-time heat recovery efficiency based on the difference between the heat exchange medium flow rate and the furnace wall temperature, and dynamically adjust the steam pressure control parameters according to the real-time heat recovery efficiency. The central control unit is used to collect real-time parameters from each unit, calculate the raw material reactivity coefficient and heat recovery efficiency, and output corresponding control commands.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. The pretreatment process of the present invention ensures the purity of the raw materials. By constructing a preliminary feedback mechanism, when the real-time reaction parameters deviate from the preset reaction parameter range or the steam system state parameters deviate from the preset steam parameter range, the raw material feed rate and the temperature gradient of the reaction zone are re-optimized until the real-time associated parameters return to the corresponding preset range, thereby achieving preliminary stable control of the reaction process. The synthesis reaction is also associated with the steam generation system, thereby achieving preliminary recovery and utilization of the reaction waste heat. 2. This invention collects real-time parameters from each unit through a central control unit, performs multi-dimensional calculations including the raw material reactivity coefficient and heat recovery efficiency, and outputs corresponding control commands based on the calculation results. This realizes fully automated operation of the entire process from raw material pretreatment, reaction optimization, heat recovery to steam upgrading, and constructs a highly integrated intelligent control system. This achieves stable control of steam output pressure, effectively reduces the overall energy consumption of the system, and ultimately produces stable, high-purity by-product steam. Attached Figure Description

[0016] Figure 1 This is a flowchart of the method for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace according to Embodiment 1 of the present invention; Figure 2 This is a flowchart illustrating the division of the reaction zone and the stepped heat recovery path in the synthesis furnace according to Embodiment 2 of the present invention. Figure 3 This is a flowchart of the optimized steam upgrading process in Embodiment 3 of the present invention. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1

[0018] Please see Figure 1 This embodiment provides a method for producing high-byproduct steam in a hydrogen chloride graphite synthesis furnace, comprising the following steps: Based on the reaction characteristics and steam production requirements of the hydrogen chloride graphite synthesis furnace, hydrogen and chlorine were selected as the reaction raw materials. The hydrogen and chlorine were introduced separately into a graphite purification device for impurity removal. The purification device removed solid particles, moisture, and other impurities from the raw materials through filtration and adsorption. Based on the purity test results of the reaction raw materials, refined hydrogen and refined chlorine with purity meeting the reaction requirements were obtained. Simultaneously, the refined hydrogen and refined chlorine were mixed according to the stoichiometric ratio of the synthesis reaction to form a mixed raw material gas. This mixed raw material gas was then passed into a preheating channel for preheating to obtain pretreated reaction raw material gas. Based on the state of the pretreated reaction feed gas, the synthesis reaction parameters are adjusted. Simultaneously, the correlation parameters between the reaction system and the steam system are collected, and the temperature and pressure distribution of the hydrogen chloride synthesis reaction are optimized based on the correlation parameters. The heat distribution released during the synthesis reaction is determined based on the optimized temperature distribution. Combined with the associated parameters, a heat recovery path is set to enhance the heat transfer between the furnace wall and the heat exchange medium in the hydrogen chloride graphite synthesis furnace. The recovered heat is obtained according to the heat recovery path and crude steam is generated. The crude steam is then subjected to steam upgrading treatment to increase the pressure and purity of the by-product steam and obtain high-yield qualified by-product steam. Specifically, in this embodiment, the control of the synthesis reaction parameters is as follows: Based on the stoichiometry and purity test results of the pretreated reaction raw material gas, the raw material reactivity coefficient is calculated, and the raw material feed rate is dynamically adjusted based on the raw material reactivity coefficient. Based on the adjusted raw material feed rate and the furnace structure characteristics of the hydrogen chloride graphite synthesis furnace, at least two reaction zones are divided, including a high-temperature reaction zone and a low-temperature transition zone. At the same time, the temperature gradient of the reaction zones is controlled: based on the real-time temperature of the high-temperature reaction zone, the heat source supply intensity of the zone is adjusted. When the temperature of the high-temperature reaction zone is lower than the reaction start-up temperature, the heat source supply is increased; when the temperature is higher than the reaction intensity threshold, the heat source supply is reduced. Simultaneously, the heat preservation intensity of the low-temperature transition zone is controlled to maintain the temperature difference between the low-temperature transition zone and the high-temperature reaction zone within the preset temperature difference range. Real-time correlation parameters within the hydrogen chloride graphite synthesis furnace are obtained, including real-time reaction parameters and steam system status parameters. The real-time reaction parameters include the temperature, furnace pressure, and raw material gas conversion rate of each reaction zone. The steam system status parameters include the outlet temperature of the heat exchange medium and the steam generation rate corresponding to the high-temperature reaction zone and the low-temperature transition zone. The stability of the reaction system and the steam system is determined based on the real-time correlation parameters. When the real-time reaction parameters deviate from the preset reaction parameter range or the steam system state parameters deviate from the preset steam parameter range, the feed rate is adjusted, and the feed rate and temperature gradient of the reaction zone are re-optimized until the real-time related parameters return to the corresponding preset range, thus maintaining the stability of the reaction system and the steam system. In this embodiment, the heating medium of the preheating channel is the low-temperature waste heat fluid of the subsequent by-product steam system. The mixed raw material gas and the low-temperature waste heat fluid exchange heat indirectly, so that the temperature of the mixed raw material gas rises to the preheating temperature required for the reaction to start. In this embodiment, when the reactivity coefficient of the raw material is lower than the preset activity threshold, the raw material feed rate is increased; when the reactivity coefficient of the raw material is higher than the preset activity threshold, the raw material feed rate is decreased, so that the raw material feed rate matches the reactivity. In this embodiment, based on the exothermic characteristics of the hydrogen chloride synthesis reaction and the steam production requirements, the raw material pretreatment stage, through impurity removal and waste heat preheating, avoids furnace wall scaling and reaction efficiency reduction caused by impurities, while utilizing system waste heat to reduce reaction start-up energy consumption. The combination of reaction parameter control and temperature and pressure optimization ensures stable exothermic reaction, providing a continuous and controllable heat source for heat recovery. The design of the connection between heat recovery and steam upgrading enables the efficient conversion of recovered heat into qualified steam, increases the per-unit-time output of by-product steam by a preset basic ratio, and ensures that the steam purity meets industrial-grade application standards. At the same time, it reduces raw material consumption and energy consumption, resulting in significant economic and environmental benefits. Example 2

[0019] To further improve the stability of the exothermic reaction and the efficiency of heat recovery, and to further increase the output of by-product steam, refer to Figure 2 As shown, based on the above embodiments, this embodiment further optimizes the temperature and pressure distribution and improves the heat recovery path.

[0020] In this embodiment, based on real-time reaction parameters and combined with the stoichiometric ratio of the synthesis reaction, the raw material ratio, heat extraction intensity and furnace pressure of the hydrogen chloride graphite synthesis furnace are dynamically controlled to match the temperature and pressure distribution within a preset optimization range. The molar ratio of hydrogen to chlorine is calculated based on the flow rate of the raw material gas. When the molar ratio deviates from the preset molar ratio range, the opening of the raw material gas inlet valve is adjusted in real time to correct the molar ratio back to the preset molar ratio range. The stoichiometric ratio of the synthesis reaction is used as the preset molar ratio range to stabilize the exothermic reaction intensity. Based on the temperatures of each reaction zone and the furnace wall temperature, the flow rate of the heat transfer medium in each reaction zone is adjusted. When the temperature of the high-temperature reaction zone exceeds the preset high-temperature threshold, the flow rate of the heat transfer medium is increased to enhance heat removal. When the temperature of the low-temperature transition zone is lower than the preset low-temperature threshold, the flow rate of the heat transfer medium is reduced to maintain the zone temperature. By adjusting the heat removal intensity differently, the temperature distribution of the reaction zone is balanced to improve the efficiency of heat transfer to the steam system. The opening of the tail gas discharge valve of the synthesis furnace is adjusted based on the furnace pressure to dynamically adjust the steam output load. Based on the raw material ratio, heat transfer intensity and furnace pressure control results, real-time temperature and pressure distribution data of hydrogen chloride synthesis reaction are obtained, and it is determined whether the real-time temperature and pressure distribution data are within the preset optimization range. When the temperature and pressure are not within the preset optimization range, the raw material ratio, heat transfer intensity, or furnace pressure parameters are adjusted until the real-time temperature and pressure distribution return to the preset optimization range, generating stable reaction heat source conditions and providing basic support for subsequent heat recovery.

[0021] In this embodiment, when the pressure inside the furnace is higher than a preset high-pressure threshold, the opening of the steam output valve is increased to increase the steam output load; when the pressure inside the furnace is lower than a preset low-pressure threshold, the opening of the steam output valve is decreased. In this embodiment, based on the temperature gradient of the reaction zone after regulation, and combined with the real-time temperature and pressure distribution data, the flow path of the heat exchange medium is optimized to match the flow path with the temperature gradient of the reaction zone. Based on the matching results, heat recovery paths are set for each reaction zone, and transition channels are set at the connection points of each reaction zone to ensure a smooth transition of the heat exchange medium between each reaction zone and avoid local heat loss caused by sudden changes in flow regime. In this embodiment, an annular flow channel is set for the high-temperature reaction zone, with at least two layers arranged along the circumference of the furnace wall. Spiral turbulence protrusions are set on the inner wall of the channel to enhance convective heat transfer with the high-temperature furnace wall by increasing the turbulence intensity of the heat transfer medium. This structure causes the heat transfer medium to form a spiral upward turbulent state in the channel, increasing the relative flow velocity and contact frequency between the medium and the high-temperature furnace wall, and enhancing the convective heat transfer efficiency. At the same time, the flow direction of the medium in the high-temperature zone channel is controlled to be opposite to the flow direction of the reaction gas, so as to maximize heat capture by utilizing the reverse heat transfer temperature difference. In this embodiment, an axial fin structure is configured for the low-temperature transition zone, with the fin roots tightly fitted to the furnace wall. This increases the heat exchange area and improves the conduction heat exchange efficiency with the low-temperature furnace wall. The fins convert the surface heat source of the furnace wall into a line heat source, increasing the contact area between the heat exchange medium and the low-temperature furnace wall. A straight guide plate is also provided between the fins to allow the heat exchange medium to flow in a laminar state along the length of the fins, thereby improving the conduction heat exchange efficiency. In this embodiment, by setting up an annular flow channel and axial fin structure, the contact area between the heat exchange medium and the furnace wall inside the hydrogen chloride graphite synthesis furnace is increased, thereby enhancing the heat transfer efficiency. This achieves efficient capture of high heat in the high-temperature zone and full recovery of residual heat in the low-temperature zone, forming a stepped heat recovery chain. This enhances the heat transfer efficiency between the furnace wall and the heat exchange medium inside the hydrogen chloride graphite synthesis furnace. By dynamically controlling the temperature and pressure distribution and combining it with the stepped heat recovery path, the heat recovery efficiency is significantly improved, providing a stable and efficient heat source for high-yield steam. Example 3

[0022] In the traditional steam treatment process of hydrogen chloride graphite synthesis furnace, there are problems such as incomplete purification of crude steam, large pressure fluctuations, and high system energy consumption, resulting in poor quality stability of by-product steam and insufficient applicability to high-end industrial scenarios.

[0023] To address the aforementioned issues, this embodiment optimizes the steam upgrading process and system control based on embodiments 1 and 2. For details, please refer to Figure 3 The steam upgrading process specifically includes: obtaining the pressure, humidity, and impurity content detection results of the crude steam, wherein the humidity data is correlated with the humidity of the steam-water mixture in the steam system state parameters; based on the detection results, using a separation device to remove condensate and trace solid impurities from the crude steam, and simultaneously adjusting the heating intensity of the steam superheating section by combining the recovered heat obtained from the heat recovery path; when the crude steam pressure is lower than a preset pressure threshold, increasing the heating intensity of the superheating section, and when the pressure is higher than the preset pressure threshold, decreasing the heating intensity, so that the steam quality meets the preset quality standards.

[0024] The process of regulating the steam output pressure includes: calculating the real-time heat recovery efficiency based on the real-time difference between the heat exchange medium flow rate and the furnace wall temperature, combined with the recovery characteristics of the heat recovery path; and dynamically adjusting the pressure regulation parameters during the steam upgrading process based on the real-time heat recovery efficiency and the pressure detection results of the crude steam, including the buffer tank pressure setpoint and the superheated section heating power, so that the output of by-product steam per unit time is increased by a predetermined ratio compared with the conventional method that does not adopt the heat recovery path design. In this embodiment, dynamically adjusting the pressure control parameters specifically includes: correcting the pressure setpoint of the buffer tank to make it positively correlated with the steam production demand and the real-time heat recovery efficiency; adjusting the heating power of the superheated section to link the heating power with the heating intensity of the superheated section; when the heat recovery efficiency is higher than the preset efficiency threshold, reducing the heating power to reduce additional energy consumption; when the heat recovery efficiency is lower than the preset efficiency threshold, increasing the heating power to compensate for insufficient heat; through the above parameter adjustments, the output of by-product steam per unit time is increased by a preset ratio compared to the conventional method without a heat recovery path, thereby achieving a high output target.

[0025] To better demonstrate a method for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace, this invention provides a system for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace, comprising: The raw material pretreatment unit includes a graphite purification device, a raw material metering and mixing device, and a waste heat preheating channel. The purification device has built-in filter components and adsorption components for removing impurities from hydrogen and chlorine to obtain refined raw material gas that meets the purity requirements. In this embodiment, the raw material metering and mixing device is used to mix refined hydrogen and refined chlorine according to the stoichiometric ratio of the synthesis reaction; the waste heat preheating channel is provided with an indirect heat exchange structure, and its heating medium input end is connected to the low-temperature waste heat output end of the steam system, which is used to preheat the mixed raw material gas to the reaction start-up temperature using low-temperature waste heat. The reaction control and temperature / pressure optimization unit includes a hydrogen chloride graphite synthesis furnace body, a raw material ratio adjustment component, a temperature gradient control component, and an in-furnace pressure control component. The synthesis furnace body is divided into a high-temperature reaction zone and a low-temperature transition zone. The raw material ratio adjustment component includes a raw material gas flow sensor and an inlet regulating valve, used to correct the molar ratio of hydrogen to chlorine in real time based on flow data. The temperature gradient control component includes temperature sensors for each reaction zone and heat source / insulation components, used to control the temperature gradient of each reaction zone. The in-furnace pressure control component includes an in-furnace pressure sensor and a tail gas discharge valve, used to dynamically adjust the steam output load based on the in-furnace pressure, optimizing the temperature and pressure distribution of the synthesis reaction. The stepped heat recovery unit includes a high-temperature zone heat exchange component, a low-temperature zone heat exchange component, and a flow transition component adapted to the furnace wall of the synthesis furnace; it is used to design differentiated heat exchange paths to match the temperature gradient of the reaction zone, capture high heat in the high-temperature zone and residual heat in the low-temperature zone, enhance heat transfer between the furnace wall and the heat exchange medium, and achieve a smooth flow transition of the heat exchange medium. The steam upgrading unit includes a crude steam detection component, a purification and separation device, and a superheating device. The purification and separation device includes a cyclone separation component and a precision filter component. It is used to collect data on the pressure, humidity, and impurity content of the crude steam, remove condensate and trace solid impurities from the crude steam, and adjust the heating intensity of the superheating section based on the recovered heat to optimize the steam pressure and purity. The steam pressure and output control unit includes a buffer tank, a heating power adjustment component, and a heat recovery efficiency detection component. The buffer tank is used to store the upgraded steam, and its pressure setpoint can be dynamically corrected based on the steam output demand and heat recovery efficiency. The heating power adjustment component is linked with the superheating device, calculates the real-time heat recovery efficiency based on the difference between the heat exchange medium flow rate and the furnace wall temperature, and dynamically adjusts the steam pressure control parameters according to the real-time heat recovery efficiency. The central control unit is used to collect real-time parameters of each unit, calculate the raw material reactivity coefficient and heat recovery efficiency, and output corresponding control commands such as raw material feed rate, ratio, heat exchange medium flow rate, and heating intensity to achieve coordinated operation of each unit and ensure high output and high quality of by-product steam.

[0026] In this embodiment, the central control unit links various functional units to calculate the real-time heat recovery efficiency based on the real-time difference between the heat exchange medium flow rate and the furnace wall temperature; the buffer tank pressure setpoint is dynamically corrected to make it positively correlated with the steam production demand and heat recovery efficiency; the superheated section heating power is adjusted, reducing the heating power when the heat recovery efficiency is higher than the preset threshold and increasing the heating power when it is lower than the preset threshold, thereby reducing additional energy consumption; at the same time, the low-temperature waste heat of the steam system is continuously introduced into the raw material preheating channel to realize the recycling of waste heat, effectively solving the problems of steam quality fluctuation and high energy consumption in traditional methods, and reducing the steam pressure fluctuation range to the preset range, effectively reducing the overall energy consumption of the system. Example 4

[0027] The determination of whether the real-time temperature and pressure distribution data are within the preset optimization range is achieved by converting the current temperature and pressure combination into a quantitative value of the physical state of the furnace wall, specifically including the following steps: Step 1: Establish a physical state quantification model based on acoustic-thermal coupling: Establish the dynamic phase transition critical index. A computational model characterizes the boiling heat transfer physical state of the heat exchange wall under specific thermal parameters; and an acoustic emission sensor is installed on the graphite furnace wall to obtain the reference acoustic spectrum energy density function under a preset standard nucleate boiling state. ; Step 2: Obtain real-time thermal and acoustic parameters acting on the furnace wall: Real-time acquisition of the acoustic spectrum energy density function of the reaction region. Simultaneously, the current steam pressure, which serves as a control parameter, is obtained. With circulating water mass flow rate The real-time local heat flux of the reaction zone was calculated based on the feed rate of the raw materials. ; Step 3: Calculate the dynamic phase transition critical index to quantify the physical state: Use the Kern-Seaton fouling deposition model to iteratively update the thickness of the fouling thermal resistance layer on the heat exchange wall in real time. The temperature and pressure combination obtained in step two is converted into a quantitative value of the current physical state using thermodynamic and acoustic formulas. The calculation formula is: in: The real-time local heat flux of the reaction region is defined as follows: ,in The total reaction heat load is calculated based on the feed rate. This is the heat distribution coefficient for the region. This is the effective heat transfer area of ​​the reaction region; Current steam pressure With circulating water mass flow rate The theoretical critical heat flux baseline value is obtained based on the modified vertical flow channel critical heat flux correlation. For time The dynamically accumulated thickness of the fouling thermal resistance layer on the heat exchange wall is based on the Kern-Seaton fouling deposition model. Perform real-time iterative updates. For model variation parameters, For sedimentation rate, Erosion rate; The thermal conductivity of the dirt layer; This is a correction factor for the effect of dirt surface roughness on bubble nucleation density; The real-time acoustic spectrum energy density function is obtained by an acoustic emission sensor installed on the graphite furnace wall. The reference acoustic spectrum energy density function is a preset standard nuclear boiling state. The characteristic frequency range for bubble coalescence is 20 kHz to 100 kHz. These are acoustic weighting coefficients; For integration variables; Step 4: Verify the stability of the heat source conditions based on quantitative numerical values: The calculated values... As a criterion, it is confirmed whether the current temperature and pressure regulation has achieved a stable heat source state, including: when Less than the preset safety threshold If the current temperature and pressure combination determines that a dangerous physical state of film boiling has been generated on the furnace wall, and it is confirmed that a stable heat source for reaction has not been generated, then the real-time temperature and pressure distribution data is not within the preset optimization range.

[0028] The core challenge in achieving high by-product steam output during the operation of a hydrogen chloride graphite synthesis furnace lies in maximizing the recovery and utilization of the enormous heat released from the chlorine and hydrogen synthesis reaction while ensuring equipment safety. This reaction process is highly exothermic, especially in the central reaction region where the graphite furnace wall must withstand extremely high heat loads. This heat is transferred through the furnace wall to the external cooling medium (usually circulating water), causing it to vaporize and generate steam. This process relies on a highly efficient boiling heat transfer mechanism. Under ideal conditions, the cooling medium is in a nucleation boiling state on the heat exchange wall surface. At this time, a large number of discrete bubbles are continuously generated on the wall surface. These bubbles quickly detach from the wall surface and carry away a large amount of latent heat, resulting in extremely high heat transfer efficiency. However, as the operating load of the synthesis furnace increases, the heat flux on the wall surface also increases. When the heat flux exceeds a certain critical value, the boiling mechanism undergoes a sudden change. Too many bubbles are generated on the wall surface, and they coalesce before they can detach, ultimately forming a continuous, unstable vapor film covering the wall surface. Because steam has a much lower thermal conductivity than liquid water, this steam film creates a huge thermal resistance, leading to a sharp drop in heat transfer efficiency. This phenomenon is known as a boiling crisis, or film boiling. Film boiling is extremely dangerous for graphite synthesis furnaces. The inability to effectively dissipate heat causes a rapid surge in graphite wall temperature, potentially exceeding the material's tolerance limits and triggering equipment burnout. Simultaneously, the output and pressure of byproduct steam fluctuate drastically. Traditional monitoring systems rely primarily on macroscopic parameters such as temperature and pressure, which exhibit significant lag in responding to boiling crises. By the time an abnormal rise in wall temperature is detected, film boiling has often already occurred, and taking emergency load reduction or furnace shutdown measures at this point results in substantial production losses. Therefore, achieving real-time quantification and early warning of film boiling risks is a key technological bottleneck for achieving high byproduct steam production.

[0029] To address this challenge, this invention introduces an advanced dynamic phase transition critical index calculation model based on acoustic-thermal coupling. This model is used to determine in real-time and accurately whether the real-time temperature and pressure distribution data within the synthesis furnace are within a preset optimization range. Its core function is to quantify the risk of film boiling on the heat exchanger walls of the synthesis furnace in real time. The working principle of this model is based on a core idea: the boiling process is not only a heat transfer phenomenon, but also accompanied by unique bubble dynamics and acoustic phenomena. By integrating real-time thermal-hydraulic parameter analysis with highly sensitive acoustic signal monitoring, it is possible to gain in-depth insight into the evolution of the microscopic boiling state of the wall, thereby capturing the precursors of film boiling before significant changes occur in macroscopic parameters.

[0030] The dynamic phase transition critical index is a dimensionless comprehensive index that intuitively reflects the safety margin between the current operating conditions and the occurrence of film boiling. The calculation of this index comprehensively considers multiple key dimensions affecting boiling heat transfer, including real-time heat load distribution, theoretical heat transfer limit, actual service condition of the heat exchange wall, and the microscopic phase transition behavior characteristics occurring on the wall.

[0031] First, the model needs to accurately quantify the real-time local heat flux of the reaction zone. This is the basis for assessing the intensity of the heat load. This invention uses a calculation method based on energy conservation and reaction kinetics to determine this value. The system calculates the total reaction heat load generated by the entire synthesis furnace at the current moment, based on the feed rate of the raw materials acquired in real time by the central control unit, combined with parameters such as the real-time concentration and conversion rate of hydrogen and chlorine. Subsequently, the system uses a pre-established heat distribution model within the synthesis furnace to determine the heat distribution coefficient of the specific reaction zone. This coefficient characterizes the proportion of heat released in that zone within the total reaction heat load. Finally, multiplying the total reaction heat load by the heat distribution coefficient of that zone and dividing by the effective heat exchange area of ​​that reaction zone yields the average real-time local heat flux on the wall of that zone. This real-time update of the parameter ensures that the model can accurately track changes in the reaction load.

[0032] Secondly, the model needs to determine a theoretical heat transfer limit baseline, namely the theoretical critical heat flux baseline. This value represents the maximum heat flux that the heat exchange wall can withstand under the current system parameters. This baseline value is determined based on the current steam pressure and the mass flow rate of the circulating water. The steam pressure determines the saturation temperature and thermal properties of the cooling medium, while the mass flow rate of the circulating water determines the convection intensity within the flow channel and the scouring effect on bubbles. The system obtains this baseline value by calling a modified critical heat flux correlation suitable for the specific vertical flow channel geometry of the graphite synthesis furnace. These correlations are mature models based on extensive experimental and theoretical analyses, capable of predicting the critical heat flux under specific operating conditions with relatively high accuracy.

[0033] However, theoretical benchmarks are typically derived from clean, smooth, ideal heat exchanger walls. In actual industrial operation, fouling and surface roughness inevitably occur on heat exchanger walls, factors that significantly affect actual heat transfer performance and critical heat flux. To make the model more closely reflect reality, this invention introduces a dynamic correction mechanism for the service conditions of the heat exchanger walls.

[0034] The model focuses on the impact of fouling thermal resistance layer on the heat exchanger wall. Over time, impurities in the cooling medium gradually deposit on the wall surface, forming a fouling layer. This invention employs a dynamic fouling deposition model, such as one based on the classic fouling deposition and erosion equilibrium principle (e.g., the Kern-Seaton fouling deposition model), to iteratively update the dynamically accumulated fouling thermal resistance layer thickness on the heat exchanger wall in real time. This model assumes that the rate of change of fouling thickness (i.e., the model variation parameter) is the difference between the fouling deposition rate and the fouling erosion rate. By monitoring and calculating these two rates in real time, the model can predict the growth of the fouling layer. Simultaneously, the model also needs to consider the thermal conductivity of the fouling layer, which determines the magnitude of the thermal resistance formed by fouling. Furthermore, the model introduces a correction factor to quantify the impact of fouling surface roughness on bubble nucleation density. The formation of the fouling layer alters the original wall microstructure, affecting the number and activity of bubble nucleation sites. By comprehensively considering the thermal resistance effect of fouling and the surface morphology effect, the model corrects the theoretical critical heat flux benchmark value to obtain a corrected critical heat flux that better reflects the actual condition of the current wall surface.

[0035] After completing the evaluation based on thermal parameters, this invention introduces acoustic emission technology, which constitutes the core innovation of the acoustic-thermal coupling model. Acoustic emission technology is a non-invasive online monitoring method that acquires information by capturing transient elastic waves generated inside or on the surface of a material due to energy release. During boiling, a series of dynamic behaviors, such as bubble nucleation, growth, oscillation, coalescence, and collapse, generate acoustic signals with specific frequencies and energies. Different boiling regions exhibit significantly different acoustic characteristics.

[0036] This system installs a high-sensitivity acoustic emission sensor array on the outer side of the graphite furnace wall to acquire acoustic signals generated during the boiling process in real time. The core acoustic analysis step of the model is to calculate the real-time acoustic spectral energy density function, which describes the distribution of acoustic signal energy at different frequencies. To correlate the acoustic signal with the boiling conditions, the model requires a reference benchmark, namely a preset reference acoustic spectral energy density function under standard nucleate boiling conditions, which represents the ideal acoustic characteristics of boiling.

[0037] The model compares and analyzes the real-time acquired acoustic spectral energy density function with a benchmark function. This comparison focuses on a specific frequency range characteristic of bubble coalescence, typically set between 20 kHz and 100 kHz. This range is chosen because when the boiling condition transitions from nucleus boiling to film boiling, the key microscopic phenomenon is the coalescence of small bubbles into larger bubble clusters or spots, and the acoustic signal excited by this process falls precisely within this high-frequency range. Therefore, monitoring changes in acoustic signal energy within this range can sensitively detect early signs of film boiling.

[0038] The model quantifies the deviation between the current boiling condition and the ideal nucleate boiling condition by calculating the ratio of the integral value of the real-time acoustic spectrum energy density function within the characteristic frequency range to the integral value of the reference acoustic spectrum energy density function within the same range (where the integral is the integration over the frequency variable). When the condition approaches film boiling, bubble coalescence intensifies, and this ratio changes significantly.

[0039] Finally, the calculation of the dynamic phase transition critical index integrates the results of thermal and acoustic analysis. The model uses an acoustic weighting coefficient to adjust the weight of acoustic information in the final index calculation. The final dynamic phase transition critical index combines real-time local heat flux, the corrected critical heat flux, and the acoustic characteristic ratio, and can simultaneously reflect the macroscopic heat load level and the microscopic boiling state.

[0040] In practical applications, the system presets a safety threshold. The central control unit calculates the dynamic phase transition critical index in real time and compares it with this safety threshold. When the calculated index is less than the preset safety threshold, the system determines that the reaction heat source conditions have entered the critical risk zone of film boiling. This means that although film boiling has not yet fully occurred, the operating conditions are very close to the critical point. At this time, the system will immediately trigger the preset unsteady-state control strategy to actively intervene. Example 5

[0041] When step four determines that a stable heat source for reaction has not been generated, an unsteady-state control strategy is triggered, specifically including executing a superheat suppression operation based on vapor pressure to correct the physical state: While maintaining a constant feed rate, the steam outlet regulating valve is opened less to achieve a preset pressure ramp-up rate. Increase the system operating pressure on the by-product steam side; Utilizing the saturation temperature caused by pressure increase Increase, decrease the superheat between the graphite wall and the cooling medium This forces the boiling condition to revert from the transition boiling zone or the film boiling initiation zone back to the nucleus boiling zone; Simultaneously, a micro-disturbance generator located outside the heat exchange channel is activated to apply a frequency similar to that of the heat exchange medium. Matching mechanical vibrations physically disrupt the air film layer formed on the heat exchange wall, until... Return to safe threshold The above confirms the conditions for restoring a stable reaction heat source.

[0042] When the dynamic phase change critical index calculation model based on acoustic-thermal coupling determines that the heat exchanger wall of the synthesis furnace is in the critical risk zone of film boiling (i.e., the index is less than the preset safety threshold), the system will immediately trigger a precise unsteady-state control strategy. The core objective of this strategy is to quickly eliminate the risk of film boiling and restore efficient and stable nucleus boiling heat transfer without interrupting the hydrogen chloride synthesis reaction and maintaining production continuity. Specifically, this strategy includes performing superheat suppression operations based on steam pressure, supplemented by mechanical micro-perturbation to enhance heat transfer.

[0043] The core idea of ​​this strategy is to address the driving force of the heat transfer process, namely superheat. Superheat is defined as the difference between the temperature of the heat exchange wall and the saturation temperature of the cooling medium. When the superheat exceeds a certain critical value, film boiling will be induced. Therefore, to eliminate the risk of film boiling, the key is to rapidly reduce the superheat of the wall. This reduction can be achieved by lowering the wall temperature or increasing the saturation temperature of the cooling medium. Traditional emergency measures typically involve reducing the feed rate to lower the wall temperature, but this can cause production fluctuations. This invention adopts an innovative technical approach: while maintaining a stable reaction load, the saturation temperature of the cooling medium is increased by actively controlling the system pressure on the by-product steam side, thereby suppressing superheat. The specific operation process is as follows: When the central control unit determines that the system is in a critical risk zone, it first issues an instruction to maintain a constant feed rate to ensure the hydrogen chloride synthesis reaction continues. Subsequently, the system immediately regulates the by-product steam system. The central control unit controls the steam outlet regulating valve to reduce its opening. As the valve opening decreases, the resistance to steam outflow increases, leading to steam accumulation within the system and thus increasing the system operating pressure on the by-product steam side. This pressure increase process is precisely controlled according to a preset pressure ramp-up rate to avoid system shocks caused by excessively rapid pressure changes.

[0044] As system pressure increases, the saturation temperature of the cooling medium also rises, according to the thermodynamic properties of water and water vapor. Higher pressure results in a higher saturation temperature. For example, when the pressure increases from one standard atmosphere to ten standard atmospheres, the saturation temperature of water rises from 100 degrees Celsius to approximately 180 degrees Celsius. By forcibly increasing the saturation temperature of the cooling medium, while the wall temperature changes relatively slowly over a short period, the difference between the wall temperature and the saturation temperature of the cooling medium—the superheat—is forced to decrease.

[0045] The reduction in superheat directly alters the boiling conditions on the wall surface. According to the boiling curve, when the superheat decreases to a certain level, the boiling conditions reverse. The conditions that were originally in the transition boiling region or the initiation region of film boiling are forced to regress to the nucleus boiling region. The microscopic mechanism of this process is as follows: as the superheat decreases, the unstable gas film or large bubble clusters that were originally covering the wall surface lose their driving force to maintain their existence. The gas film ruptures, and the liquid re-contacts the high-temperature wall surface, restoring efficient nucleus boiling heat transfer. The restoration of heat transfer efficiency allows for effective control of the wall temperature, and may even begin to decrease, thereby completely eliminating the risk of film boiling.

[0046] However, in certain extreme cases, simply increasing pressure may not be sufficient to quickly break the already formed stable gas film. To further enhance the heat transfer recovery process and ensure the effectiveness and speed of the control strategy, this invention introduces auxiliary mechanical micro-perturbation methods.

[0047] While performing superheat suppression, the system activates micro-disturbance generators located outside the heat exchange channels. These devices apply high-frequency, low-amplitude mechanical vibrations to the heat exchange channels. The mechanism of these mechanical vibrations is to physically disrupt the gas film layer formed on the heat exchange wall surface.

[0048] In this invention, the applied mechanical vibration frequency is experimentally designed in advance. The vibration frequency applied by the micro-perturbation generator is set to match the characteristic frequency range of bubble coalescence determined in the aforementioned dynamic phase transition critical index calculation model, typically within the range of 20 kHz to 100 kHz. The reason for choosing this frequency range is that vibrations within this range can resonate or strongly couple with the natural frequency of the bubbles or the coalescence process, thereby achieving the maximum destructive effect with minimal energy input.

[0049] Mechanical vibration triggers a series of complex hydrodynamic effects within the heat exchange channel. First, vibration generates pressure waves and velocity pulsations in the cooling medium, creating intense turbulence and secondary flows that directly impact the vapor film adhering to the wall surface. Second, vibration induces interfacial instabilities, such as Rayleigh-Taylor instability and Kelvin-Helmholtz instability. These instabilities cause fluctuations and deformations at the vapor-liquid interface; when the fluctuation amplitude is sufficiently large, the vapor film ruptures. Third, high-frequency vibration can also induce cavitation and acoustic flow effects, further impacting and disrupting the vapor film and accelerating the rewetting process of the wall surface.

[0050] The introduction of mechanical micro-perturbations, combined with pressure-based superheat suppression, creates a powerful synergistic effect. Superheat suppression thermodynamically weakens the conditions for film formation, while mechanical micro-perturbations kinetically accelerate the film rupture process. This combination ensures that the system can rapidly and reliably return to safe nucleate boiling conditions when a risk of film boiling is detected.

[0051] Throughout the execution of the unsteady-state control strategy, the central control unit continuously monitors the changes in the dynamic phase transition critical index in real time. Once the index returns to above the safe threshold and remains stable for a period of time, the system determines that the risk of film boiling has been eliminated. At this point, the unsteady-state control strategy ends. The micro-disturbance generator stops working, the opening of the steam outlet regulating valve gradually returns to the normal set value, and the system pressure on the by-product steam side also smoothly returns to the normal operating pressure.

[0052] The entire process achieved undisturbed handling of the boiling crisis, ensuring the continuous, stable, and high-load operation of the hydrogen chloride synthesis furnace, and providing a solid guarantee for achieving high by-product steam output.

[0053] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace, characterized in that, Includes the following steps: Based on the reaction characteristics and steam production requirements of the hydrogen chloride graphite synthesis furnace, hydrogen and chlorine were selected as the reaction feed gases, and the reaction feed gases were pretreated. Based on the state of the pretreated reaction feed gas, the synthesis reaction parameters are adjusted, and the correlation parameters between the reaction system and the steam system are collected. The temperature and pressure distribution of the hydrogen chloride synthesis reaction are optimized based on the correlation parameters. The heat distribution released during the synthesis reaction is determined based on the optimized temperature distribution. A heat recovery path is set in conjunction with the associated parameters. The recovered heat is obtained and crude steam is generated according to the heat recovery path. The crude steam is then subjected to steam upgrading treatment to obtain high-yield qualified by-product steam.

2. The method for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace as described in claim 1, characterized in that, The raw material pretreatment specifically includes: Hydrogen and chlorine are introduced into a graphite purification device to remove impurities. Based on the purity test results of the reaction raw material gas, refined hydrogen and refined chlorine with purity meeting the reaction requirements are obtained. Simultaneously, refined hydrogen and refined chlorine are mixed according to the stoichiometric ratio of the synthesis reaction to form a mixed raw material gas, which is then passed into a preheating channel for preheating to obtain a pretreated reaction raw material gas.

3. The method for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace as described in claim 2, characterized in that, The control of the synthesis reaction parameters is specifically as follows: Based on the stoichiometry and purity test results of the pretreated reaction raw material gas, the raw material reactivity coefficient is calculated, and the raw material feed rate is dynamically adjusted based on the raw material reactivity coefficient. Based on the adjusted raw material feed rate and combined with the furnace structure characteristics of the hydrogen chloride graphite synthesis furnace, divide the reaction zone into no less than two zones, and simultaneously control the temperature gradient of the reaction zone. Real-time correlation parameters within the hydrogen chloride graphite synthesis furnace are obtained, including real-time reaction parameters and steam system state parameters, and the stability of the reaction system and steam system is determined based on the real-time correlation parameters. Among them, the real-time reaction parameters include the temperature of each reaction zone, the pressure inside the furnace and the conversion rate of the raw material gas, and the steam system status parameters include the outlet temperature of the heat exchange medium and the steam generation rate corresponding to the high temperature reaction zone and the low temperature transition zone. When the real-time reaction parameters deviate from the preset reaction parameter range or the steam system state parameters deviate from the preset steam parameter range, the feed rate and temperature gradient of the reaction zone are re-optimized until the real-time related parameters return to the corresponding preset range.

4. A method for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace as described in claim 3, characterized in that, Optimizing the temperature and pressure distribution of the hydrogen chloride synthesis reaction specifically includes: Based on real-time reaction parameters and combined with the stoichiometric ratio of the synthesis reaction, the raw material ratio, heat transfer intensity and furnace pressure of the hydrogen chloride graphite synthesis furnace are dynamically controlled to match the temperature and pressure distribution within the preset optimization range. The molar ratio of hydrogen to chlorine is calculated based on the flow rate of the raw material gas. When the molar ratio deviates from the preset molar ratio range, the opening of the raw material gas inlet valve is adjusted in real time to correct the molar ratio and bring it back to the preset molar ratio range. Based on the temperature of each reaction zone and the furnace wall temperature, the flow rate of the heat transfer medium in each reaction zone of the heat recovery device is adjusted, and the opening of the tail gas discharge valve of the synthesis furnace is adjusted based on the furnace pressure to dynamically adjust the steam output load. Based on the raw material ratio, heat transfer intensity and furnace pressure control results, real-time temperature and pressure distribution data of the hydrogen chloride synthesis reaction are obtained, and it is determined whether the real-time temperature and pressure distribution data are within the preset optimization range. When the target temperature and pressure are not within the preset optimization range, adjust the raw material ratio, heat transfer intensity, or furnace pressure parameters until the real-time temperature and pressure distribution return to the preset optimization range, generating stable reaction heat source conditions.

5. A method for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace as described in claim 4, characterized in that, The heat recovery path is specifically as follows: Based on the temperature gradient of the reaction zone after regulation, and combined with the real-time temperature and pressure distribution data, the flow path of the heat exchange medium is optimized to match the flow path with the temperature gradient of the reaction zone. Based on the matching results, heat recovery paths are set for each reaction zone, and transition channels are set at the connection points of each reaction zone to ensure a smooth transition of the heat exchange medium between the reaction zones.

6. A method for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace as described in claim 5, characterized in that, The steam upgrading process specifically includes: The pressure, humidity, and impurity content of the crude steam are obtained, wherein the humidity data is correlated with the humidity of the steam-water mixture in the steam system state parameters; Based on the detection results, condensate and trace solid impurities in the crude steam are removed, and the heating intensity of the steam superheating section is adjusted by combining the recovered heat obtained from the heat recovery path. When the crude steam pressure is lower than the preset pressure threshold, the heating intensity of the superheated section is increased; when the pressure is higher than the preset pressure threshold, the heating intensity is reduced so that the steam quality meets the preset quality standard.

7. A method for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace as described in claim 6, characterized in that, The process of regulating the steam output pressure includes: Based on the real-time difference between the heat exchange medium flow rate and the furnace wall temperature, and combined with the recovery characteristics of the heat recovery path, the real-time heat recovery efficiency is calculated. Based on the real-time heat recovery efficiency and the pressure detection results of the crude steam, the pressure control parameters during the steam upgrading process are dynamically adjusted.

8. A method for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace as described in claim 4, characterized in that, The determination of whether the real-time temperature and pressure distribution data are within the preset optimization range is achieved by converting the current temperature and pressure combination into a quantitative value of the physical state of the furnace wall, specifically including the following steps: Step 1: Establish a physical state quantification model based on acoustic-thermal coupling: Establish the dynamic phase transition critical index. A computational model characterizes the boiling heat transfer physical state of the heat exchange wall under specific thermal parameters; and an acoustic emission sensor is installed on the graphite furnace wall to obtain the reference acoustic spectrum energy density function under a preset standard nucleate boiling state. ; Step 2: Obtain real-time thermal and acoustic parameters acting on the furnace wall: Real-time acquisition of the acoustic spectrum energy density function of the reaction region. Simultaneously, the current steam pressure, which serves as a control parameter, is obtained. With circulating water mass flow rate The real-time local heat flux of the reaction zone was calculated based on the feed rate of the raw materials. ; Step 3: Calculate the dynamic phase transition critical index to quantify the physical state: Use the Kern-Seaton fouling deposition model to iteratively update the thickness of the fouling thermal resistance layer on the heat exchange wall in real time. The temperature and pressure combination obtained in step two is converted into a quantitative value of the current physical state using thermodynamic and acoustic formulas. The calculation formula is: in: The real-time local heat flux of the reaction region is defined as follows: ,in The total reaction heat load is calculated based on the feed rate. This is the heat distribution coefficient for the region. This is the effective heat transfer area of ​​the reaction region; Current steam pressure With circulating water mass flow rate The theoretical critical heat flux baseline value is obtained based on the modified vertical flow channel critical heat flux correlation. For time The dynamically accumulated thickness of the fouling thermal resistance layer on the heat exchange wall is based on the Kern-Seaton fouling deposition model. Perform real-time iterative updates. For model variation parameters, For sedimentation rate, Erosion rate; The thermal conductivity of the dirt layer; This is a correction factor for the effect of dirt surface roughness on bubble nucleation density; The real-time acoustic spectrum energy density function is obtained by an acoustic emission sensor installed on the graphite furnace wall. The reference acoustic spectrum energy density function is a preset standard nuclear boiling state. The characteristic frequency range for bubble coalescence is 20 kHz to 100 kHz. These are acoustic weighting coefficients; For integration variables; Step 4: Verify the stability of the heat source conditions based on quantitative numerical values: The calculated values... As a criterion, it is confirmed whether the current temperature and pressure regulation has achieved a stable heat source state, including: when Less than the preset safety threshold If the current temperature and pressure combination determines that a dangerous physical state of film boiling has been generated on the furnace wall, and it is confirmed that a stable heat source for reaction has not been generated, then the real-time temperature and pressure distribution data is not within the preset optimization range.

9. A method for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace as described in claim 8, characterized in that, When step four determines that a stable heat source for reaction has not been generated, an unsteady-state control strategy is triggered, specifically including executing a superheat suppression operation based on vapor pressure to correct the physical state: While maintaining a constant feed rate, the steam outlet regulating valve is opened less to achieve a preset pressure ramp-up rate. Increase the system operating pressure on the by-product steam side; Utilizing the saturation temperature caused by pressure increase Increase, decrease the superheat between the graphite wall and the cooling medium This forces the boiling condition to revert from the transition boiling zone or the film boiling initiation zone back to the nucleus boiling zone; Simultaneously, a micro-disturbance generator located outside the heat exchange channel is activated to apply a frequency consistent with... Matching mechanical vibrations physically disrupt the air film layer formed on the heat exchange wall, until... Return to safe threshold The above confirms the conditions for restoring a stable reaction heat source.

10. A system for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace, applied in the method for producing high-by-product steam in a hydrogen chloride graphite synthesis furnace as described in claim 7, characterized in that, include: The raw material pretreatment unit is used to remove impurities from hydrogen and chlorine to obtain refined raw material gas that meets the purity requirements. The reaction control and temperature and pressure optimization unit is used to correct the molar ratio of hydrogen and chlorine in real time based on flow data, control the temperature gradient of each reaction zone, dynamically adjust the steam output load based on the furnace pressure, and optimize the temperature and pressure distribution of the synthesis reaction. The stepped heat recovery unit is used to design differentiated heat exchange paths to match the temperature gradient of the reaction zone, capture high heat in the high-temperature zone and residual heat in the low-temperature zone, enhance heat transfer between the furnace wall and the heat exchange medium, and achieve a smooth flow transition of the heat exchange medium. The steam upgrading unit is used to collect data on the pressure, humidity, and impurity content of crude steam, remove condensate and trace solid impurities from the crude steam, and adjust the heating intensity of the superheated section based on the recovered heat to optimize the steam pressure and purity. The steam pressure and output control unit is used to store the upgraded steam, calculate the real-time heat recovery efficiency based on the difference between the heat exchange medium flow rate and the furnace wall temperature, and dynamically adjust the steam pressure control parameters according to the real-time heat recovery efficiency. The central control unit is used to collect real-time parameters from each unit, calculate the raw material reactivity coefficient and heat recovery efficiency, and output corresponding control commands.

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