A green oxygen purification and air separation oxygen collaborative oxygen supply system and method for pulverized coal gasification

Abstract

The application relates to a green oxygen purification and air separation oxygen collaborative oxygen supply system and method for pulverized coal gasification, and the system comprises the following: a green oxygen purification module for continuously purifying by-product green oxygen generated in water electrolysis; an end quality detection module for detecting indexes of the purified green oxygen; a directional reflux module for connecting a reflux branch to the front end of different processing units in the green oxygen purification module to continue purifying the green oxygen; a qualified green oxygen buffer module for receiving and stabilizing the qualified green oxygen; an air separation oxygen supply module for making up the oxygen gap when the green oxygen fluctuates or the green oxygen system is abnormal; and an oxygen gas allocation module for mixing and allocating the qualified green oxygen and the air separation oxygen. The green oxygen purification module, the end quality detection module, the directional reflux module, the qualified green oxygen buffer module, the air separation oxygen supply module and the oxygen gas allocation module are collaboratively controlled and adjusted, efficient utilization of the green oxygen is realized, directional purification correction is realized, air separation oxygen compensation supply is realized, and the pulverized coal gasification furnace is stably operated.

Description

Technical Field

[0001] This application relates to the field of coal chemical production technology, and in particular to a green oxygen purification and air separation oxygen synergistic oxygen supply system and method for pulverized coal gasification. Background Technology

[0002] Pulverized coal gasification is a crucial upstream process in modern coal chemical industry. Pulverized coal gasifiers typically require a continuous and stable oxygen supply to maintain stable furnace temperature, oxygen-to-coal ratio, carbon conversion rate, and syngas composition. Existing coal chemical plants largely rely on air separation units for oxygen. While air separation oxygen production technology is mature and provides a stable supply, it involves significant investment, high energy consumption, and prolonged high-load operation increases the operating costs of the coal chemical system.

[0003] With the development of renewable energy hydrogen production technology, oxygen is produced as a byproduct at the anode during the water electrolysis hydrogen production process. This oxygen originates from the green electricity hydrogen production process and can be referred to as green oxygen. Green oxygen has high utilization value; if it can be used in the pulverized coal gasification process, it can, to some extent, replace air separation oxygen, reduce the load on the air separation unit, and improve the resource utilization level of byproduct oxygen in the green hydrogen system.

[0004] However, the green oxygen produced as a byproduct of water electrolysis cannot be directly connected to the oxygen supply system of a pulverized coal gasifier. The quality of the green oxygen can be affected by factors such as the type of electrolyzer, operating load, start-up and shutdown status, diaphragm or membrane electrode state, gas-liquid separation efficiency, and system pressure fluctuations. This can result in issues such as fluctuations in oxygen purity, trace hydrogen entrainment, high moisture content, electrolyte droplet entrainment, particulate matter entrainment, and pressure and flow rate fluctuations. If it is directly integrated into the main oxygen pipeline of a coal chemical plant without stabilization treatment, it may affect the stability of the oxygen pipeline network and the operational safety of the pulverized coal gasifier.

[0005] While existing technologies have addressed issues such as high-purity electrolytic oxygen, coupling of green oxygen with air separation systems, green oxygen participation in coal gasification, macroscopic coupling of wind-solar-hydrogen energy storage with coal chemical industry, safety control of oxygen production systems, and gas-liquid separation in electrolysis, the following shortcomings still exist: (1) There is a lack of a scheme to purify the green oxygen by-product of water electrolysis from easy to difficult according to the difficulty of removing impurities; (2) There is a lack of a scheme to conduct comprehensive testing of the quality of green oxygen at the end of the green oxygen purification process; (3) There is a lack of a scheme to direct unqualified green oxygen back to the front end of the corresponding purification unit based on the end test results, and there is also a lack of a scheme to avoid repeated purification of all unqualified green oxygen and reduce the secondary purification load; (4) There is a lack of a scheme to accurately adjust the green oxygen and air separation oxygen supply ratio according to the pulverized coal feed rate of the pulverized coal gasifier, the target oxygen-coal ratio, the gasifier load and the oxygen header pressure. Summary of the Invention

[0006] This application provides a green oxygen purification and air separation oxygen co-supply system and method for pulverized coal gasification. Through the coordinated control and regulation of green oxygen purification unit, end quality detection module, directional reflux module, qualified green oxygen buffer module, air separation oxygen supply module, and oxygen distribution module, the system achieves efficient utilization of green oxygen, directional purification correction, and air separation oxygen compensation supply, thereby ensuring the stable operation of the pulverized coal gasifier.

[0007] This application provides a green oxygen purification and air separation oxygen co-supply system for pulverized coal gasification, comprising the following modules: a green oxygen purification module, whose inlet is connected to the source of green oxygen produced by water electrolysis, for continuously purifying the green oxygen produced by water electrolysis according to the principle of impurity particle size from large to small; an end-of-pipe quality detection module, whose inlet is connected to the outlet of the green oxygen purification module, for detecting the quality indicators and operating indicators of the purified green oxygen; a directional reflux module, whose inlet is connected to the unqualified green oxygen outlet of the end-of-pipe quality detection module, and whose outlet is connected to the front end of different processing units in the green oxygen purification module and / or the inlet of the green oxygen purification module through multiple reflux branches; and a qualified green oxygen buffer module, whose inlet is connected to the qualified green oxygen outlet of the end-of-pipe quality detection module, for receiving and... The system includes: a stable green oxygen supply module (after passing a stable test); an air separation oxygen supply module (whose inlet receives air separation oxygen from the air separation oxygen generator to supplement oxygen supply when there is insufficient green oxygen, pressure and flow fluctuations, or system malfunctions); an oxygen blending module (connected to the outlets of the qualified green oxygen buffer module and the air separation oxygen supply module to mix and blend qualified green oxygen with air separation oxygen); a pressure stabilizing buffer module (whose inlet is connected to the outlet of the oxygen blending module, and whose outlet is connected to the oxygen supply pipeline of the pulverized coal gasifier); and a control module (connected to the end-of-line quality detection module, the directional reflux module, the qualified green oxygen buffer module, the air separation oxygen supply module, the oxygen blending module, the pulverized coal feed rate signal source, and the gasifier load signal source).

[0008] Optionally, the green oxygen purification module includes, in sequence along the gas flow purification direction: a gas-liquid separation unit for removing free droplets, condensate, and some electrolyte droplets through gravity settling, cyclone separation, or baffle separation; a demisting filtration unit for removing aerosol water mist and fine droplets through inertial collision, interception, coalescence, and gravity drainage; an electrolyte droplet collection unit for collecting electrolyte droplets entrained in the green oxygen; a condensation and dehydration unit for cooling the green oxygen to a set condensation temperature and discharging condensate; an adsorption drying unit for deep drying the condensed and dehydrated green oxygen; a selective catalytic dehydrogenation unit for reacting trace amounts of hydrogen and oxygen in the green oxygen to generate water; a post-reaction dehydration unit for removing the water generated by the selective catalytic dehydrogenation reaction; and a precision filtration unit for removing desiccant dust, catalyst dust, and pipeline particles to obtain pure green oxygen.

[0009] Optionally, the end-of-line quality detection module includes one or more quality index detectors and operational index detectors connected in parallel: the quality index detectors include: oxygen purity detector, hydrogen detector, dew point meter or trace water analyzer, droplet detector, conductivity detector, alkaline mist detector, and particulate matter detector; the operational index detectors include: pressure detection element and flow detection element; the control module outputs qualified, reflux, or switching control commands based on the comparison between the detection results of each instrument and the set threshold; wherein, the set threshold is set based on the strictest of the following criteria: oxygen design parameters for the gasifier, safety requirements for the main oxygen pipeline, allowable impurity levels of downstream nozzles, and enterprise process control indicators.

[0010] Optionally, the directional reflux module includes: a droplet reflux branch connected to the front end of the gas-liquid separation unit; a mist droplet reflux branch connected to the front end of the demisting filter unit; an electrolyte mist droplet reflux branch connected to the front end of the electrolyte mist droplet collection unit; a dehydration reflux branch connected to the front end of the condensation dehydration unit or the adsorption drying unit; a dehydrogenation reflux branch connected to the front end of the selective catalytic dehydrogenation unit; a particulate matter reflux branch connected to the front end of the precision filter unit; and a comprehensive reflux branch connected to the inlet of the green oxygen purification module or the front end of the corresponding front-end non-compliant indicator treatment unit; each reflux branch is equipped with a switching valve or regulating valve controlled by the control module, as well as pressure detection elements and flow detection elements.

[0011] Optionally, the oxygen distribution module includes: a green oxygen branch, an air separation oxygen branch, a green oxygen flow regulating valve disposed on the green oxygen branch, an air separation oxygen flow regulating valve disposed on the air separation oxygen branch, and an oxygen mixer; the upstream of the green oxygen branch is connected to the qualified green oxygen buffer module, the upstream of the air separation oxygen branch is connected to the air separation oxygen supply module, and the downstream of the two branches merges into the oxygen mixer.

[0012] Optionally, the control module is configured such that: the total oxygen demand of the pulverized coal gasifier is determined based on the product of the pulverized coal feed rate and the oxygen consumption per unit of pulverized coal; wherein, the oxygen consumption per unit of pulverized coal is determined based on the coal type, gasifier load, target furnace temperature, and syngas composition requirements; the smaller of the available qualified green oxygen and the total oxygen demand is used as the actual supply of qualified green oxygen, and the proportion of qualified green oxygen supply is prioritized to be increased; when the available qualified green oxygen is greater than or equal to the total oxygen demand, oxygen is supplied entirely by qualified green oxygen; when the actual supply of qualified green oxygen is lower than the total oxygen demand, the difference is made up by air separation oxygen, which is described by the formula: air separation oxygen supply = total oxygen demand of pulverized coal gasifier - actual supply of qualified green oxygen.

[0013] Optionally, the control module is further configured to: reduce the qualified green oxygen supply ratio or cut off the green oxygen branch when any or more of the terminal quality detection module, the directional reflux module, and the green oxygen purification module malfunction and / or the pressure of the qualified green oxygen buffer module is lower than the set value and / or the flow rate of the qualified green oxygen buffer module is lower than the set value, and the air separation oxygen supply module supplies oxygen to the pulverized coal gasifier alone; when unqualified green oxygen still cannot meet the set requirements after directional reflux treatment, it is cut off from the system and enters the safety venting or temporary storage module, while the air separation oxygen supply module maintains the oxygen supply to the pulverized coal gasifier; when the oxygen mixer pressure is lower than the set value, the air separation oxygen supply is increased; when the oxygen mixer pressure is higher than the set value, the opening degree of the qualified green oxygen or air separation oxygen branch valve is reduced.

[0014] This application provides a method for co-supplying green oxygen purification and air separation oxygen in pulverized coal gasification, comprising the following steps: S201: Green oxygen generated during water electrolysis hydrogen production is introduced into a green oxygen purification module, and sequentially undergoes gas-liquid separation, demisting filtration, electrolyte droplet capture, condensation and dehydration, adsorption drying, selective catalytic dehydrogenation, post-reaction dehydration, and precision filtration to remove impurities; S202: The purified green oxygen is introduced into an end-of-line quality detection module to detect its oxygen purity, hydrogen content, moisture content, droplet or mist entrainment, and particulate matter content; S203 If all test results meet the set requirements, the green oxygen is sent to the qualified green oxygen buffer module; if at least one indicator does not meet the set requirements, the unqualified green oxygen is sent back to the front end or inlet of the corresponding processing unit in the green oxygen purification module through the directional reflux module for reprocessing until the test is qualified; S204: The qualified green oxygen output from the qualified green oxygen buffer module and the air separation oxygen output from the air separation oxygen supply module are mixed and blended in the oxygen blending module, wherein the qualified green oxygen is used first, and the insufficient part is supplemented by air separation oxygen; S205: The mixed oxygen, after being buffered and stabilized by the pressure stabilizing module, is sent to the oxygen supply pipeline of the pulverized coal gasifier.

[0015] Optionally, step S202 includes: collecting quality indicators such as oxygen purity, hydrogen content, moisture content, droplet or mist entrainment, and particulate matter content of the purified green oxygen, as well as operating indicators such as pressure and flow rate, from the control module; obtaining detection results based on the quality indicators and operating indicators collected by the end-point quality detection module; comparing the detection results with the set threshold, and outputting qualified, recirculation, or switching control commands.

[0016] Optionally, in step S203, if at least one indicator fails to meet the set requirements, the unqualified green oxygen is returned to the front end of the corresponding processing unit in the green oxygen purification module via a directional reflux module, depending on the type of the unqualified indicator. This includes: when the amount of free droplets entrained does not meet the set requirements, it is returned to the front end of the gas-liquid separation unit; when the amount of aerosol water mist entrained does not meet the set requirements, it is returned to the front end of the demisting filter unit; when the amount of electrolyte droplets entrained does not meet the set requirements, it is returned to the front end of the electrolyte droplet collection unit; when the moisture content does not meet the set requirements, it is returned to the front end of the condensation dehydration unit or the adsorption drying unit; when the hydrogen content does not meet the set requirements, it is returned to the front end of the selective catalytic dehydrogenation unit; when the particulate matter content does not meet the set requirements, it is returned to the front end of the precision filtration unit; when two or more indicators fail to meet the set requirements, it is returned to the inlet of the green oxygen purification module or the front end of the corresponding unqualified indicator processing unit.

[0017] This application has at least the following advantages: This application primarily proposes a tiered purification process for the green oxygen produced as a byproduct of hydrogen production through water electrolysis. This process, from easy to difficult, is first purified by a green oxygen purification module, reducing the load on subsequent purification units. An end-of-line quality inspection module is placed at the end of the green oxygen purification process to directly determine whether the purified green oxygen meets the oxygen requirements for pulverized coal gasification. For green oxygen that fails the test, a directional reflux module is used to send it back to the corresponding purification unit for reprocessing based on the non-compliance indicators, avoiding redundant purification of all green oxygen. The qualified green oxygen is then coordinated with air-separated oxygen, prioritizing the use of green oxygen while using air-separated oxygen to compensate for oxygen supply fluctuations, achieving a stable oxygen supply to the pulverized coal gasifier. This method reduces ineffective redundant purification, improves green oxygen utilization, reduces air-separated oxygen consumption, enhances the adaptability of the coal chemical system to renewable energy byproduct oxygen, and ensures the continuous and stable operation of the pulverized coal gasifier without altering the main structure of the pulverized coal gasifier. Attached Figure Description

[0018] Figure 1 The following is a structural block diagram of a green oxygen purification and air separation oxygen synergistic oxygen supply system for pulverized coal gasification in one embodiment; Figure 2 This is a schematic diagram illustrating the green oxygen purification and end-of-pipe detection process in one embodiment; Figure 3 This is a schematic diagram illustrating the sequence determination of directional reflux in one embodiment; Figure 4 This is a schematic flowchart illustrating a method for co-supplying green oxygen purification and air separation oxygen in pulverized coal gasification, as shown in one embodiment. Detailed Implementation

[0019] The present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the scope of the present application.

[0020] Figure 1 A structural block diagram of a green oxygen purification and air separation oxygen co-supply system for pulverized coal gasification provided in this application embodiment is provided. The system may include: The green oxygen purification module has an inlet for connecting to the source of green oxygen produced by water electrolysis. It is used to continuously purify the green oxygen produced by water electrolysis according to the principle of purifying impurities from large to small particle size. The end-of-pipe quality testing module has its inlet connected to the outlet of the green oxygen purification module and is used to test the quality indicators and operating indicators of the purified green oxygen. The directional reflux module has its inlet connected to the unqualified green oxygen outlet of the end quality inspection module, and its outlet is connected to the front end of different processing units in the green oxygen purification module and / or the inlet of the green oxygen purification module through multiple reflux branches. The qualified green oxygen buffer module has its inlet connected to the qualified green oxygen outlet of the end quality detection module, and is used to receive and stabilize the qualified green oxygen after detection. The air separation oxygen supply module has an inlet for receiving air separation oxygen output from the air separation oxygen generator, which replenishes the oxygen supply gap when the green oxygen supply is insufficient, pressure and flow fluctuate, or the green oxygen system is abnormal. The oxygen blending module is connected to the outlet of the qualified green oxygen buffer module and the outlet of the air separation oxygen supply module, respectively, and is used to mix and blend qualified green oxygen with air separation oxygen. The pressure stabilizing and buffering module has its inlet connected to the outlet of the oxygen distribution module, and its outlet is used to connect to the oxygen supply pipeline of the pulverized coal gasification furnace. The control module is connected to the end-of-line quality detection module, the directional reflux module, the qualified green oxygen buffer module, the air separation oxygen supply module, the oxygen distribution module, the pulverized coal feed rate signal source, and the gasifier load signal source, respectively.

[0021] In this embodiment, the green oxygen produced as a byproduct of hydrogen production through water electrolysis is first treated by a green oxygen purification module, and then assessed by a terminal quality detection module to determine whether it meets the oxygen requirements for coal chemical industry. Unqualified green oxygen can be directed back to the corresponding purification unit for further treatment based on specific problem indicators. The qualified green oxygen is then supplied to the pulverized coal gasifier in conjunction with air-separated oxygen. This method can improve green oxygen utilization, reduce air-separated oxygen consumption, and provide targeted purification correction and air-separated oxygen compensation without altering the main structure of the pulverized coal gasifier. This enhances the adaptability of the coal chemical system to renewable energy byproduct oxygen, ensuring stable operation of the pulverized coal gasifier.

[0022] The following is a detailed explanation of each module: Please refer to Figure 2As shown, the green oxygen purification module has its inlet connected to the source of green oxygen produced by water electrolysis. It is used to continuously purify the green oxygen produced by water electrolysis according to the principle of purifying impurities from large to small particle size.

[0023] In one feasible implementation, the green oxygen purification module includes a gas-liquid separation unit, a demisting and filtration unit, an electrolyte droplet collection unit, a condensation and dehydration unit, an adsorption and drying unit, a selective catalytic dehydrogenation unit, a post-reaction dehydration unit, and a precision filtration unit. These units are arranged sequentially along the gas flow purification direction, and are arranged in order of increasing importance based on the form of impurities, removal difficulty, impact on subsequent equipment, and purification cost.

[0024] When green oxygen is discharged from the water electrolysis system, it may initially carry larger free droplets. These droplets can be easily removed through gravity settling, cyclone separation, or baffle separation. Without prior separation, the processing load on subsequent demisting, drying, and catalytic dehydrogenation units will increase, and may even cause liquid accumulation in pipelines and equipment corrosion. Therefore, a gas-liquid separation unit is first installed to remove free droplets. This unit may include a separation cylinder, cyclone or baffle components, a liquid level detection element, and a drain port, used to remove free droplets, condensate, and some electrolyte droplets through gravity settling, cyclone separation, or baffle separation.

[0025] Even after gas-liquid separation, small-particle-size, highly suspended aerosol water mist and fine droplets may still remain in the green oxygen solution. These droplets are difficult to completely remove through ordinary gas-liquid separation and require further capture using methods such as wire mesh demisters, fiber interception, or coalescing filtration. If these droplets continue to enter subsequent units, they will affect the electrolyte droplet capture effect and increase the desiccant load. Therefore, a demisting and filtering unit is installed after the gas-liquid separation unit. The demisting and filtering unit may include a wire mesh demister, a baffle plate demister, a fiber demister, a cyclone demister, or a coalescing filter, used to remove aerosol water mist and fine droplets through inertial impaction, interception, coalescence, and gravity drainage.

[0026] The electrolyte droplet collection unit may include a hydrophilic fiber collection layer, an alkali-resistant coalescing filter element, an ultrapure water washing section, an alkali mist absorption packing layer, or a combination thereof. It is used to collect KOH, NaOH, or other electrolyte droplets entrained in the green oxygen solution. These droplets not only corrode pipes and valves but may also cover the active sites of the catalyst in the selective catalytic dehydrogenation unit, leading to catalyst contamination, deactivation, or increased bed pressure drop. The electrolyte droplet collection unit shall have a collection efficiency of no less than 99.5% for electrolyte droplets, and the electrolyte droplet content in the treated green oxygen shall not exceed 1 mg / Nm³. 3 .

[0027] The condensation and dehydration unit may include a cooler, a condenser, a gas-liquid separator, a drain outlet, and a temperature detection element. It is used to cool the green oxygen to a set condensation temperature, such as 2 to 10 °C, so that some of the water vapor in it condenses into liquid water, which is then discharged through the gas-liquid separator and the drain outlet, thereby initially reducing the moisture content in the green oxygen and the processing load of the subsequent adsorption and drying unit.

[0028] The adsorption drying unit may include a molecular sieve dryer, an activated alumina dryer, a silica gel dryer, or a composite desiccant bed, and is preferably configured as a dual-tower alternating operation structure for deep drying of the condensed and dehydrated green oxygen, ensuring that the pressure dew point of the green oxygen at the outlet of the adsorption drying unit does not exceed [a certain value]. 60 ℃; when the dew point at the outlet of the adsorption tower is higher than 60 ℃; When the temperature reaches 60 ℃ or the preset adsorption cycle is reached, the control module switches between the operating adsorption tower and the standby adsorption tower.

[0029] The selective catalytic dehydrogenation unit may include a catalytic reactor, a palladium-based catalyst, a platinum-based catalyst, a palladium-platinum composite catalyst, or a metal oxide composite catalyst, as well as inlet temperature, outlet temperature, and bed pressure differential detection elements. It is used to react trace amounts of hydrogen and oxygen in the green oxygen to produce water. The reaction temperature of the selective catalytic dehydrogenation unit is controlled at 80–200 °C, and the gas hourly space velocity (GHSV) is controlled at 1000–5000 h⁻¹. -1 When the pressure difference in the catalyst bed reaches or exceeds 20 kPa, the control module outputs a bed pressure difference alarm signal.

[0030] The post-reaction dehydration unit may include a condenser, an adsorption dryer, or a combination of both, to remove the water generated in the selective catalytic dehydrogenation reaction and prevent the water generated in the reaction from affecting the final moisture content index.

[0031] The precision filtration unit may include a microporous filter, a sintered metal filter element, a polytetrafluoroethylene filter element, or an oxygen-resistant filter element, and is used to remove desiccant dust, catalyst dust, and pipeline particulate matter, so that the green oxygen reaches a stable purification state before entering the end quality detection module.

[0032] Thus, through the above treatment, the main impurities in the green oxygen are removed step by step in order of increasing difficulty. This achieves step-by-step purification from easily separable impurities to difficult-to-treat impurities, from liquid entrainment to gaseous impurities, and from front-end load reduction to back-end equipment protection. This ensures that the green oxygen reaches a relatively stable purification state before entering the end-of-line quality detection module, and provides a reliable gas source for the subsequent co-supply of qualified green oxygen and air separation oxygen to the pulverized coal gasification furnace.

[0033] Please continue to refer to Figure 2As shown, the end-of-pipe quality detection module has its inlet connected to the outlet of the green oxygen purification module. It is used to detect the quality indicators and operating indicators of the purified green oxygen. The end-of-pipe quality detection module includes one or more quality indicator detectors and operating indicator detectors connected in parallel.

[0034] The end-point quality control module detects oxygen purity, hydrogen content, moisture content, electrolyte droplet entrainment, particulate matter content, pressure, and flow rate. The various end-point quality control items can be performed in parallel online, without requiring the gas to pass through each detection instrument sequentially for judgment. Based on commands from the control module, the end-point quality control module first collects quality indicators such as oxygen purity, hydrogen content, moisture content, droplet or mist entrainment, and particulate matter content from the quality indicator detectors, then collects operational indicators such as pressure and flow rate from the operational indicator detectors, and finally outputs pass, reflux, or switching control commands based on set thresholds.

[0035] Specifically, in one feasible approach, oxygen purity can be obtained using an oxygen purity detector, hydrogen content can be obtained using a hydrogen detector, moisture content can be obtained using a dew point meter or trace water analyzer, the presence of droplets, water mist, or electrolyte droplets can be obtained using a droplet detector, conductivity detector, alkaline mist detector, or online sampling, particulate matter content can be obtained using a particulate matter detector or with the assistance of a filter differential pressure signal, and pressure and flow rate can be obtained using pressure sensing elements and flow rate sensing elements, respectively. Finally, based on the detection results of each instrument and the set thresholds, a pass, reflux, or switching control command is output. The pass thresholds for oxygen purity are no less than 99.5%, for hydrogen content no more than 0.5%, and for moisture content measured using a pressure dew point meter no more than... At 60 ℃, the electrolyte droplet content should not exceed 1 mg / Nm³, and the particulate matter content should not exceed 1 mg / Nm³. 3 When any of the above quality indicators continuously exceeds the corresponding set threshold for a preset judgment delay of 10-60 seconds, the control module determines that the corresponding quality indicator is unqualified and activates the corresponding directional reflux branch according to the type of unqualified indicator; preferably, the preset judgment delay is 30 seconds. This reduces the probability of misjudgment or frequent switching of control valves caused by instantaneous fluctuations in the detection signal.

[0036] Additionally, it should be noted that when a particular application scenario has control requirements for other impurities, corresponding testing items can be added to the end-of-line quality inspection module.

[0037] After being tested by the end-of-line quality inspection module, if the test results meet the oxygen setting requirements for coal chemical pulverized coal gasification, the control module determines the green oxygen as qualified green oxygen and sends it to the qualified green oxygen buffer module. If at least one indicator in the test results does not meet the oxygen setting requirements for coal chemical pulverized coal gasification, the control module determines the green oxygen as unqualified green oxygen and starts the directional reflux module according to the type of unqualified indicator.

[0038] Please refer to Figure 2 , Figure 3 As shown, the directional reflux module has its inlet connected to the unqualified green oxygen outlet of the end quality inspection module, and its outlet connected to the front end of different treatment units in the green oxygen purification module and / or the inlet of the green oxygen purification module through multiple reflux branches. The directional reflux module specifically includes: The droplet reflux branch is connected to the front end of the gas-liquid separation unit; The droplet return branch is connected to the front end of the demisting filter unit; The electrolyte droplet return branch is connected to the front end of the electrolyte droplet collection unit; The dehydration reflux branch is connected to the front end of the condensation dehydration unit or the adsorption drying unit; The dehydrogenation reflux branch is connected to the front end of the selective catalytic dehydrogenation unit; The particulate matter return branch is connected to the front end of the precision filter unit; And the integrated return branch, which connects to the inlet of the green oxygen purification module or the front end of the corresponding front-end non-compliant indicator processing unit; Each return branch is equipped with a switch valve or regulating valve controlled by the control module, as well as pressure detection elements and flow detection elements.

[0039] The entire reflux sequence described above is processed according to the principle of processing impurities from largest to smallest that need to be purified. For example, the entrainment amounts of free droplets, aerosol water mist, and electrolyte droplets are all sub-indicators of "droplet, water mist, or electrolyte droplet entrainment" in the end-of-pipe quality inspection. Among them, since the entrainment amount of free droplets mainly corresponds to the entrainment of larger droplets or condensate, the entrainment amount of aerosol water mist mainly corresponds to the entrainment of fine suspended water mist or fine droplets, and the entrainment amount of electrolyte droplets mainly corresponds to the entrainment of droplets containing KOH, NaOH, or other electrolytes, the reflux sequence is: first gas-liquid separation, then demisting filtration, and finally electrolyte droplet collection.

[0040] Specifically, in one feasible manner, when the end-of-line quality inspection module detects that the amount of free droplets entrained does not meet the set requirements, the control module opens the droplet reflux branch, allowing the unqualified green oxygen to flow back to the front end of the gas-liquid separation unit.

[0041] When the end-of-line quality inspection module detects that the amount of aerosol water mist entrained does not meet the set requirements, the control module opens the droplet return branch, allowing the unqualified green oxygen to flow back to the front end of the defogging filter unit.

[0042] When the end-of-line quality inspection module detects that the amount of electrolyte droplets entrained does not meet the set requirements, the control module opens the electrolyte droplet reflux branch, allowing the unqualified green oxygen to flow back to the front end of the electrolyte droplet collection unit.

[0043] When the end-of-line quality inspection module detects that the moisture content does not meet the set requirements, the control module opens the dehydration reflux branch, allowing the unqualified green oxygen to flow back to the front end of the condensation dehydration unit or the adsorption drying unit.

[0044] When the end-of-line quality detection module detects that the hydrogen content does not meet the set requirements, the control module opens the dehydrogenation reflux branch, causing the unqualified green oxygen to flow back to the front end of the selective catalytic dehydrogenation unit.

[0045] When the end-of-line quality inspection module detects that the particulate matter content does not meet the set requirements, the control module opens the particulate matter return branch, allowing the unqualified green oxygen to flow back to the front end of the precision filter unit.

[0046] When the end-of-line quality inspection module detects that two or more indicators fail to meet the set requirements, the control module opens the integrated reflux branch, allowing the substandard green oxygen to preferentially reflux to the corresponding front-end substandard indicator processing unit, and if necessary, reflux to the green oxygen purification unit inlet. Here, the corresponding front-end substandard indicator processing unit refers to the purification unit that can handle the corresponding substandard indicator and is located at the very beginning of the purification process. For example, substandard droplets correspond to the gas-liquid separation unit, substandard water mist to the demisting filtration unit, substandard electrolyte droplets to the electrolyte droplet collection unit, substandard moisture to the condensation dehydration unit or adsorption drying unit, substandard hydrogen to the selective catalytic dehydrogenation unit, and substandard particulate matter to the precision filtration unit. In one example, when both moisture and hydrogen are substandard, because the moisture processing unit is located before the selective catalytic dehydrogenation unit, it can preferentially reflux to the condensation dehydration unit or the front end of the adsorption drying unit; when droplets, water mist, or electrolyte droplets are substandard simultaneously, it can reflux to the front end of the gas-liquid separation unit or the green oxygen purification unit inlet to ensure that entrained substances at the very beginning are removed first. Compared with the treatment method of returning all unqualified green oxygen to the purification inlet or directly discharging it, this application determines the reprocessing location according to the unqualified indicators. This can reduce the repeated load on irrelevant purification units, shorten the reprocessing path, and reduce energy consumption and equipment wear.

[0047] After undergoing directional reflux treatment, the green oxygen enters the end-of-pipe quality testing module again. Once it passes the test, it enters the qualified green oxygen buffer module.

[0048] Please refer to Figure 1 , Figure 2As shown, the qualified green oxygen buffer module has its inlet connected to the qualified green oxygen outlet of the end quality detection module, which is used to receive and stabilize qualified green oxygen.

[0049] In one feasible implementation, the qualified green oxygen buffer module includes a qualified green oxygen buffer tank, a pressure regulating valve, a check valve, a flow regulating valve, a pressure sensing element, a flow sensing element, and a safety relief valve. An exhaust valve, sampling port, and pressure regulating valve, check valve, and safety relief valve can be added as needed. The inlet of the qualified green oxygen buffer module is connected to the qualified green oxygen outlet of the end-of-line quality inspection module, and the outlet of the qualified green oxygen buffer module is connected to the green oxygen branch of the oxygen distribution module. Its specific function is to temporarily store, stabilize the pressure and flow of qualified green oxygen through a buffer tank, pressure stabilizing valve, check valve, and flow regulating valve, preventing short-term fluctuations from the water electrolysis hydrogen production unit or green oxygen purification module from being directly transmitted to the oxygen distribution module. The buffer tank is used to contain qualified green oxygen and reduce flow fluctuations, the pressure stabilizing valve is used to maintain the outlet pressure, the check valve is used to prevent backflow of air-separated oxygen or mixed oxygen, the flow regulating valve is used to regulate the green oxygen supply, the pressure detection element and the flow detection element are used to provide operating signals to the control module, and the safety relief valve is used for overpressure protection, thereby meeting the access requirements of the oxygen distribution module and ensuring the stable operation of the qualified green oxygen branch.

[0050] Please refer to Figure 1 As shown, the air separation oxygen supply module has an inlet for receiving air separation oxygen output from the air separation oxygen generator, which replenishes the oxygen supply gap when there is insufficient green oxygen supply, pressure and flow fluctuations, or abnormalities in the green oxygen system.

[0051] In one feasible implementation, the air separation oxygen supply module and the qualified green oxygen buffer module are connected in parallel as oxygen sources, both connected to the oxygen distribution module, rather than in series. Qualified green oxygen is preferentially utilized as a byproduct of renewable energy generation, while air separation oxygen serves as a stable compensation oxygen source, supplementing oxygen demand when green oxygen supply is insufficient, pressure and flow fluctuate, or the green oxygen system malfunctions. The air separation oxygen output from the air separation oxygen generator enters the air separation oxygen supply module. The air separation oxygen supply module includes an air separation oxygen buffer tank, an air separation oxygen pressure regulating valve, an air separation oxygen flow regulating valve, a check valve, and a safety shut-off valve.

[0052] As a stable oxygen source, air-separated oxygen (SSE) replenishes the oxygen required by the pulverized coal gasifier when there is insufficient supply of qualified green oxygen, fluctuations in qualified green oxygen pressure, malfunctions in the green oxygen purification system, or when the green oxygen flow rate is lower than the set value. Whether SSE supplementation is needed can be determined based on the following criteria: when the available flow rate of qualified green oxygen is less than the total oxygen demand of the pulverized coal gasifier, or when the qualified green oxygen buffer pressure is lower than the set lower limit, or when the flow rate of the green oxygen branch is lower than the set lower limit, or when any critical component of the end-of-pipe quality detection, directional reflux, or green oxygen purification module malfunctions or triggers an interlock alarm, the control module reduces the proportion of qualified green oxygen supply and increases the supply of SSE. If the quality of the qualified green oxygen is substandard and cannot be restored promptly through directional reflux, the control module cuts off the green oxygen branch, and SSE supplies oxygen solely.

[0053] Compared to simply incorporating air separation oxygen and electrolysis by-product oxygen into the gasifier, this embodiment links air separation oxygen compensation with end-of-pipe quality detection, qualified green oxygen buffer pressure, actual green oxygen flow rate, and total oxygen demand of the pulverized coal gasifier. This ensures continuous and stable oxygen supply to the gasifier while prioritizing the consumption of qualified green oxygen, avoiding deviations in the oxygen-coal ratio or pressure fluctuations in the oxygen distribution module caused by fluctuations in green oxygen.

[0054] Please continue to refer to Figure 1 As shown, the oxygen mixing module is connected to the outlet of the qualified green oxygen buffer module and the outlet of the air separation oxygen supply module, respectively, and is used to mix and mix qualified green oxygen and air separation oxygen. It includes: green oxygen branch, air separation oxygen branch, green oxygen flow regulating valve installed on the green oxygen branch, air separation oxygen flow regulating valve installed on the air separation oxygen branch, and oxygen mixer or mixing head pipe.

[0055] In one feasible implementation, qualified green oxygen enters the green oxygen branch of the oxygen blending module from the qualified green oxygen buffer module, and air-separated oxygen enters the air-separated oxygen branch of the oxygen blending module from the air-separated oxygen supply module. The oxygen blending module specifically includes a green oxygen branch, an air-separated oxygen branch, a green oxygen flow regulating valve, an air-separated oxygen flow regulating valve, a pressure regulating valve, a check valve, a mixing header inlet, pressure detection elements, flow detection elements, oxygen purity detection elements, hydrogen detection elements, and valve actuators connected to the control module. Before entering the oxygen mixer, the oxygen purity of the qualified green oxygen is not less than 99.5%, and the oxygen purity of the air-separated oxygen is not less than 99.6%. Both oxygen streams are pressure-regulated before entering the oxygen mixer, and the pressure difference between the two oxygen streams before mixing is controlled within 0.05 MPa, with check valves preventing backflow between the two oxygen streams. The upstream of the green oxygen branch connects to a qualified green oxygen buffer module, and the upstream of the air separation oxygen branch connects to an air separation oxygen supply module. The downstream of both branches merges into the inlet of the mixed oxygen header. Qualified green oxygen mixes with air separation oxygen and enters the mixed oxygen header, then passes through a pressure stabilizing buffer module before entering the pulverized coal gasification furnace oxygen supply pipeline. The outlet of the mixed oxygen header is equipped with oxygen purity detection elements, hydrogen detection elements, and pressure detection elements to re-verify the quality of the mixed oxygen. The oxygen purity of the mixed oxygen is controlled to be no less than 99.5%, the hydrogen content is controlled to be no more than 0.5%, and the outlet pressure of the mixed oxygen header is controlled within the target set pressure ±0.05 MPa. When the quality of the mixed oxygen does not meet the above requirements, the control module restricts or cuts off the green oxygen supply and increases the air separation oxygen supply ratio until the mixed oxygen returns to the set range.

[0056] Please refer to Figure 1 As shown, the pressure stabilizing and buffering module has its inlet connected to the outlet of the oxygen distribution module, and its outlet is used to connect to the oxygen supply pipeline of the pulverized coal gasification furnace.

[0057] In one feasible implementation, the blended oxygen enters the mixed oxygen main pipe and, after passing through the pressure stabilizing and buffering module, is sent to the oxygen supply line of the pulverized coal gasifier. The inlet of the pressure stabilizing and buffering module is connected to the outlet of the mixed oxygen main pipe, and the outlet of the pressure stabilizing and buffering module is connected to the oxygen supply line of the pulverized coal gasifier. The pressure stabilizing and buffering unit specifically includes a pressure stabilizing and buffering tank, an inlet check valve, a pressure regulating valve, a flow regulating valve, a pressure detection element, a flow detection element, a safety relief valve, a vent valve, and necessary condensate drain ports. Its function is to buffer, stabilize the pressure, and stabilize the flow rate of the mixed oxygen output from the oxygen blending module, reducing pressure fluctuations generated during the mixing of qualified green oxygen and air separation oxygen and valve adjustment, so that the oxygen flow rate and pressure entering the main oxygen line or oxygen nozzle of the pulverized coal gasifier are maintained within the set range.

[0058] In addition, the oxygen supply pipeline of the pulverized coal gasifier is equipped with an oxygen shut-off valve, an oxygen flow meter, an oxygen pressure control valve, and an emergency shut-off valve to ensure the safe operation of the gasifier.

[0059] Please refer to Figure 1 As shown, the control module is connected to the end-of-line quality detection module, directional reflux module, qualified green oxygen buffer module, air separation oxygen supply module, oxygen distribution module, pulverized coal feed rate signal source, and gasifier load signal source, respectively. The control module is configured as follows: The total oxygen demand of the pulverized coal gasifier is determined based on the pulverized coal feed rate and the oxygen consumption per unit of pulverized coal. The smaller of the available qualified green oxygen supply and the total oxygen demand shall be used as the actual supply of qualified green oxygen, and priority shall be given to increasing the proportion of qualified green oxygen supply. When the actual supply of qualified green oxygen is lower than the total oxygen demand, the air separation oxygen supply is determined. The output of the air separation oxygen supply module is controlled based on the obtained air separation oxygen supply amount.

[0060] In one feasible implementation, the control module determines the total oxygen demand of the pulverized coal gasifier based on the pulverized coal feed rate, target oxygen-to-coal ratio, gasifier load, target furnace temperature, and oxygen header pressure. The total oxygen demand of the pulverized coal gasifier can be determined according to the following relationship: Total oxygen demand = pulverized coal feed rate × oxygen consumption per unit of pulverized coal.

[0061] The oxygen consumption per unit of pulverized coal is determined based on the coal type, gasifier load, target furnace temperature, and syngas composition requirements. When the supply of qualified green oxygen meets part or all of the total oxygen demand, the control module prioritizes increasing the proportion of qualified green oxygen supply. The actual supply of qualified green oxygen can be the smaller value between the available qualified green oxygen and the total oxygen demand of the pulverized coal gasifier. When the actual supply of qualified green oxygen is lower than the total oxygen demand of the pulverized coal gasifier, the air separation oxygen automatically supplements the remaining oxygen demand. The air separation oxygen supply can be determined according to the following relationship: Oxygen supply for air separation = Total oxygen demand of pulverized coal gasification furnace - Actual supply of qualified green oxygen; The above formula is used to determine the theoretical oxygen replenishment amount for air separation, which is the basis for the proportional control of the oxygen distribution module. In specific control, the control module first determines the total oxygen demand of the pulverized coal gasifier based on the pulverized coal feed rate and the oxygen consumption per unit of pulverized coal. Then, it determines the actual supply of qualified green oxygen based on the available qualified green oxygen supply. Finally, it determines the air separation oxygen supply based on the difference. Based on this, the target pressure of the mixed oxygen main pipe and the target total oxygen flow rate of the pulverized coal gasifier are used as closed-loop control targets. When the actual pressure of the mixed oxygen main pipe is more than 0.05 MPa lower than the target set pressure, the control module prioritizes increasing the opening of the air separation oxygen flow regulating valve; when the actual pressure of the mixed oxygen main pipe is more than 0.05 MPa higher than the target set pressure, the control module decreases the opening of the flow regulating valves of the green oxygen branch and / or the air separation oxygen branch. When the actual total oxygen flow rate is lower than the total oxygen demand of the pulverized coal gasifier, the oxygen supply of the air separation unit is increased; when the actual total oxygen flow rate is higher than the total oxygen demand of the pulverized coal gasifier, the oxygen supply of the air separation unit is reduced or the total oxygen supply of the two lines is reduced accordingly, so that the pressure of the mixed oxygen main pipe and the total oxygen supply flow rate are restored to the set range.

[0062] Qualified green oxygen and air separation oxygen are mixed in the oxygen blending module and then enter the mixed oxygen header. The control module adjusts the green oxygen flow regulating valve and the air separation oxygen flow regulating valve according to the pressure of the mixed oxygen header, the gasifier load, and the oxygen flow requirements to keep the oxygen flow and pressure entering the pulverized coal gasifier stable.

[0063] In addition, the control module is configured to: when any or more modules of the end-of-line quality detection module, directional reflux module, and green oxygen purification module malfunction and / or the pressure of the qualified green oxygen buffer module is lower than the set value and / or the flow rate of the qualified green oxygen buffer module is lower than the set value, the control module determines that the green oxygen branch does not have stable oxygen supply conditions, reduces the qualified green oxygen supply ratio or cuts off the green oxygen branch, and supplies oxygen to the pulverized coal gasifier solely by the air separation oxygen supply module; when unqualified green oxygen still cannot meet the set requirements after directional reflux treatment, it is cut off from the system and enters the safety venting or temporary storage module, while the air separation oxygen supply module maintains the oxygen supply to the pulverized coal gasifier; when the oxygen mixer pressure is lower than the set value, the air separation oxygen supply is increased; when the oxygen mixer pressure is higher than the set value, the opening of the qualified green oxygen or air separation oxygen branch valve is reduced to restore the oxygen mixer pressure to the set range.

[0064] It should be noted that the control module in this embodiment is an industrial process control system, including but not limited to distributed control systems (DCS), programmable logic controllers (PLCs), or fieldbus control systems (FCS). Based on the hardware platform of the industrial control system, the control module acquires 4-20mA analog or digital signals from field instruments via I / O cards, performs calculations according to preset control logic (including ratio control, cascade control, interlocking logic, etc.), and outputs control commands to field actuators (such as regulating valves, frequency converters, etc.).

[0065] In one example, the control module includes a field signal acquisition unit, a control processing unit, and a command output unit: On-site signal acquisition unit: Receives 4-20mA current signals from pulverized coal feed rate signal source (such as pulverized coal flow meter) and gasifier load signal source (such as load setter output) via analog input card.

[0066] Control and processing unit: A DCS / PLC controller is used to process the acquired signals.

[0067] Command output unit: Through analog output card or digital output card, the calculation results are output to actuators such as pulverized coal feed rate regulating valve and oxygen regulating valve.

[0068] The implementation principle of this embodiment is as follows: The green oxygen produced as a byproduct of hydrogen production through water electrolysis is first processed by a green oxygen purification module. This purification process is designed as a graded process from easy to difficult, ensuring that droplets, water mist, electrolyte droplets, moisture, hydrogen, and particulate matter in the green oxygen are processed sequentially, reducing the load on subsequent purification units. A quality detection module is placed at the end of the green oxygen purification process to directly determine whether the purified green oxygen meets the oxygen requirements for pulverized coal gasification. For green oxygen that fails the test, a directional reflux module is set up to send it back to the front end of the corresponding purification unit for reprocessing based on the non-compliance indicators, avoiding repeated purification of all green oxygen. The qualified green oxygen and air separation oxygen are coordinated and allocated. While prioritizing the use of green oxygen, air separation oxygen compensates for oxygen supply fluctuations. The ratio of green oxygen to air separation oxygen is adjusted according to the pulverized coal feed rate, target oxygen-to-coal ratio, gasifier load, and oxygen header pressure to achieve stable oxygen supply to the pulverized coal gasifier. This method can reduce ineffective repeated purification, improve green oxygen utilization, reduce air separation oxygen consumption, enhance the adaptability of coal chemical system to renewable energy by-product oxygen, and ensure the continuous and stable operation of pulverized coal gasifier without changing the main structure of pulverized coal gasifier.

[0069] Reference Figure 4 As shown in the embodiments of this application, a method for supplying oxygen to pulverized coal gasification using green oxygen produced by water electrolysis is also provided, comprising the following steps: S201. The green oxygen generated during the water electrolysis hydrogen production process is introduced into the green oxygen purification module, and then passes through gas-liquid separation, demisting filtration, electrolyte droplet capture, condensation and dehydration, adsorption and drying, selective catalytic dehydrogenation, post-reaction dehydration and precision filtration to remove impurities. S202. The purified green oxygen is passed into the end-of-line quality detection module to detect its oxygen purity, hydrogen content, moisture content, droplet or mist entrainment and particulate matter content. S203. If all test results meet the set requirements, the green oxygen will be sent to the qualified green oxygen buffer module. If at least one indicator does not meet the set requirements, the unqualified green oxygen will be sent back to the front end or inlet of the corresponding processing unit in the green oxygen purification module through the directional reflux module for reprocessing until the test is qualified. S204. The qualified green oxygen output from the qualified green oxygen buffer module and the air separation oxygen output from the air separation oxygen supply module are mixed and blended in the oxygen blending module, with the qualified green oxygen being used first and the air separation oxygen making up the shortfall. S205. After the mixed oxygen is buffered and stabilized by the pressure stabilizing module, it is sent to the oxygen supply pipeline of the pulverized coal gasifier.

[0070] Further, in step S203, the process of returning the non-compliant green oxygen to the front end of the corresponding processing unit according to the type of non-compliant indicator specifically includes: when the amount of free droplets entrained does not meet the set requirements, it is returned to the front end of the gas-liquid separation unit; when the amount of aerosol water mist entrained does not meet the set requirements, it is returned to the front end of the demisting filter unit; when the amount of electrolyte droplets entrained does not meet the set requirements, it is returned to the front end of the electrolyte droplet collection unit. When the moisture content is detected to be below the set requirements, it is returned to the condensation dehydration unit or the front end of the adsorption drying unit; when the hydrogen content is detected to be below the set requirements, it is returned to the front end of the selective catalytic dehydrogenation unit. After selective catalytic dehydrogenation treatment, the green oxygen continues to enter the post-reaction dehydration unit to remove the moisture generated during the dehydrogenation reaction, and then re-enters the end quality detection unit for re-inspection; when the particulate matter content is detected to be below the set requirements, it is returned to the front end of the precision filtration unit; when two or more indicators are detected to be below the set requirements, it is returned to the inlet of the green oxygen purification module or the front end of the corresponding front-end non-conforming indicator treatment unit.

[0071] Further, in step S204, the qualified green oxygen output from the qualified green oxygen buffer module and the air separation oxygen output from the air separation oxygen supply module are mixed and blended in the oxygen blending module. Qualified green oxygen is used preferentially, and any shortfall is supplemented by air separation oxygen. Specifically, the total oxygen demand of the pulverized coal gasifier is determined based on the product of the pulverized coal feed rate and the oxygen consumption per unit of pulverized coal. The oxygen consumption per unit of pulverized coal is determined based on the coal type, gasifier load, target furnace temperature, and syngas composition requirements. When the available qualified green oxygen is greater than or equal to the total oxygen demand, it is supplied entirely by qualified green oxygen. When the available qualified green oxygen is less than the total oxygen demand, air separation oxygen is used to make up the difference.

[0072] The specific embodiments described above do not constitute a limitation on the scope of protection of this application. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A green oxygen purification and air separation oxygen co-supply device for pulverized coal gasification, characterized in that, include: The green oxygen purification module has its inlet connected to the source of green oxygen produced as a byproduct of water electrolysis. It is used to continuously purify the green oxygen produced by water electrolysis according to the principle of purifying impurities from largest to smallest particle size. The end-point quality inspection module, whose inlet is connected to the outlet of the green oxygen purification module, is used to detect the quality indicators and operational indicators of the purified green oxygen. The directional reflux module has its inlet connected to the non-conforming green oxygen outlet of the end-of-line quality inspection module, and its outlet connected to the front end of different processing units in the green oxygen purification module and / or the inlet of the green oxygen purification module through multiple reflux branches. The qualified green oxygen buffer module has its inlet connected to the qualified green oxygen outlet of the end quality detection module, and is used to receive and stabilize qualified green oxygen. The air separation oxygen supply module receives air separation oxygen from the air separation oxygen generator at its inlet, supplementing the oxygen supply gap when there is insufficient green oxygen supply, pressure and flow fluctuations, or abnormalities in the green oxygen system. An oxygen blending module is connected to the outlet of the qualified green oxygen buffer module and the outlet of the air separation oxygen supply module, respectively, and is used to mix and blend qualified green oxygen with air separation oxygen. A pressure stabilizing and buffering module is included, with its inlet connected to the outlet of the oxygen distribution module. The outlet of the pressure stabilizing and buffering module is used to connect to the oxygen supply pipeline of the pulverized coal gasification furnace. The control module is connected to the end quality detection module, the directional reflux module, the qualified green oxygen buffer module, the air separation oxygen supply module, the oxygen distribution module, the pulverized coal feed rate signal source, and the gasifier load signal source, respectively. The green oxygen purification module includes, in sequence, the following components along the gas flow purification direction: The gas-liquid separation unit is used to remove free droplets, condensate, and some electrolyte droplets through gravity sedimentation, cyclone separation, or baffle separation. The demisting filter unit is used to remove aerosol water mist and fine droplets through inertial impaction, interception, coalescence, and gravity drainage. Electrolyte droplet collection unit, used to collect electrolyte droplets entrained in green oxygen. The condensation and dehydration unit is used to cool the green oxygen to the set condensation temperature and discharge the condensate. The adsorption drying unit is used for deep drying of the green oxygen after condensation and dehydration. The selective catalytic dehydrogenation unit is used to react trace amounts of hydrogen and oxygen in green oxygen to produce water. The post-reaction dehydration unit is used to remove water generated by the selective catalytic dehydrogenation reaction. And a precision filtration unit, used to remove desiccant dust, catalyst dust and pipeline particles to obtain pure green oxygen; The directional return module includes: The droplet reflux branch is connected to the front end of the gas-liquid separation unit. The droplet return branch is connected to the front end of the demisting filter unit. The electrolyte droplet return branch is connected to the front end of the electrolyte droplet collection unit. The dehydration reflux branch is connected to the front end of the condensation dehydration unit or the adsorption drying unit. The dehydrogenation reflux branch is connected to the front end of the selective catalytic dehydrogenation unit. The particulate matter return branch is connected to the front end of the precision filter unit. And a comprehensive return branch, connected to the inlet of the green oxygen purification module or the front end of the corresponding front-end non-compliance indicator processing unit. Each return branch is equipped with a switching valve or regulating valve controlled by the control module, as well as pressure detection elements and flow detection elements; When the amount of free droplets entrained does not meet the set requirements, the liquid is returned to the front end of the gas-liquid separation unit. When the amount of aerosol water mist entrained does not meet the set requirements, it flows back to the front end of the demisting filter unit. When the electrolyte droplet entrainment level is detected to be below the set requirement, the electrolyte is returned to the front end of the electrolyte droplet collection unit. When the detected moisture content does not meet the set requirements, it is returned to the condensation dehydration unit or the front end of the adsorption drying unit. When the hydrogen content is detected to be below the set requirement, it is refluxed to the front end of the selective catalytic dehydrogenation unit. After selective catalytic dehydrogenation treatment, the green oxygen continues to enter the post-reaction dehydration unit to remove the water generated during the dehydrogenation reaction. When the detected particulate matter content does not meet the set requirements, it is returned to the front end of the precision filter unit. When two or more indicators are detected as not meeting the set requirements, the flow is returned to the inlet of the green oxygen purification module or the front end of the corresponding non-compliant indicator processing unit.

2. The apparatus according to claim 1, characterized in that, The end-point quality inspection module includes one or more quality indicator detectors and operational indicator detectors connected in parallel: Quality indicator testing instruments include: oxygen purity detector, hydrogen detector, dew point meter or trace water analyzer, droplet detector, conductivity detector, alkaline mist detector, and particulate matter detector. The performance indicator testing instrument includes: pressure detection element and flow detection element; The control module compares the detection results of each testing instrument with a set threshold and outputs pass, return, or switching control commands; wherein, The threshold is set based on the strictest of the following criteria: oxygen design parameters for the gasifier, safety requirements for the main oxygen pipeline, allowable impurity levels for downstream nozzles, and enterprise process control indicators.

3. The apparatus according to claim 1, characterized in that, The oxygen blending module includes: The system includes a green oxygen branch, an air separation oxygen branch, a green oxygen flow regulating valve installed on the green oxygen branch, an air separation oxygen flow regulating valve installed on the air separation oxygen branch, and an oxygen mixer; the upstream of the green oxygen branch is connected to the qualified green oxygen buffer module, the upstream of the air separation oxygen branch is connected to the air separation oxygen supply module, and the downstream of the two branches merges into the oxygen mixer.

4. The apparatus according to claim 1, characterized in that, The control module is configured as follows: The total oxygen demand of the pulverized coal gasifier is determined by the product of the pulverized coal feed rate and the oxygen consumption per unit of pulverized coal; wherein, the oxygen consumption per unit of pulverized coal is determined based on the coal type, gasifier load, target furnace temperature, and syngas composition requirements. The smaller of the available qualified green oxygen supply and the total oxygen demand shall be used as the actual supply of qualified green oxygen, and priority shall be given to increasing the proportion of qualified green oxygen supply. When the available amount of qualified green oxygen is greater than or equal to the total oxygen demand, oxygen is supplied entirely by qualified green oxygen. When the actual supply of qualified green oxygen is lower than the total oxygen demand, air separation oxygen is used to make up the difference, as described by the formula: Oxygen supply for air separation = Total oxygen demand of pulverized coal gasification furnace - Actual supply of qualified green oxygen.

5. The apparatus according to claim 1, characterized in that, The control module is also configured to: When any or more of the terminal quality detection module, the directional reflux module, and the green oxygen purification module malfunction, and / or the pressure of the qualified green oxygen buffer module is lower than the set value, and / or the flow rate of the qualified green oxygen buffer module is lower than the set value, the qualified green oxygen supply ratio is reduced or the green oxygen branch is cut off, and the air separation oxygen supply module supplies oxygen to the pulverized coal gasifier alone. When the unqualified green oxygen still cannot meet the set requirements after directional reflux treatment, it is cut out of the system and enters the safe venting or temporary storage module, while the air separation oxygen supply module maintains the oxygen supply to the pulverized coal gasifier. When the oxygen mixer pressure is lower than the set value, increase the air separation oxygen supply; when the oxygen mixer pressure is higher than the set value, reduce the opening of the qualified green oxygen or air separation oxygen branch valve.

6. An oxygen supply method using the apparatus as described in any one of claims 1 to 5, characterized in that, Includes the following steps: S201. The green oxygen generated during the water electrolysis hydrogen production process is introduced into the green oxygen purification module, and then passes through gas-liquid separation, demisting filtration, electrolyte droplet capture, condensation and dehydration, adsorption and drying, selective catalytic dehydrogenation, post-reaction dehydration and precision filtration to remove impurities. S202. The purified green oxygen is passed into the end-of-line quality detection module to detect its oxygen purity, hydrogen content, moisture content, droplet or mist entrainment and particulate matter content. S203. If all test results meet the set requirements, the green oxygen is sent to the qualified green oxygen buffer module; if at least one indicator does not meet the set requirements, the unqualified green oxygen is sent back to the front end of the corresponding processing unit in the green oxygen purification module or the inlet of the green oxygen purification module for reprocessing, according to the type of unqualified indicator, until the test is qualified. S204. The qualified green oxygen output from the qualified green oxygen buffer module and the air separation oxygen output from the air separation oxygen supply module are mixed and blended in the oxygen blending module, with the qualified green oxygen being used first and the air separation oxygen making up the shortfall. S205. After the mixed oxygen is buffered and stabilized by the pressure stabilizing module, it is sent to the oxygen supply pipeline of the pulverized coal gasifier.

7. The oxygen supply method according to claim 6, characterized in that, Step S202 includes: The control module collects quality indicators such as oxygen purity, hydrogen content, moisture content, droplet or mist entrainment, and particulate matter content of the purified green oxygen, as well as operating indicators such as pressure and flow rate. Based on the quality indicators and operational indicators collected by the end-of-line quality inspection module, the inspection results are obtained. The detection result is compared with the set threshold, and a pass, return, or switching control command is output.

8. The oxygen supply method according to claim 6, characterized in that, In step S203, if at least one indicator fails to meet the set requirements, then according to the type of non-compliant indicator, the non-compliant green oxygen is sent back to the front end of the corresponding processing unit in the green oxygen purification module or the inlet of the green oxygen purification module for reprocessing until it passes the test, including: When the amount of free droplets entrained does not meet the set requirements, it flows back to the front end of the gas-liquid separation unit. When the amount of aerosol water mist entrained does not meet the set requirements, it is returned to the front end of the demisting filter unit. When the amount of electrolyte droplets entrained does not meet the set requirements, it flows back to the front end of the electrolyte droplet collection unit. When the moisture content is detected to be below the set requirements, it is returned to the front end of the condensation dehydration unit or the adsorption drying unit. When the hydrogen content is detected to be below the set requirements, it is refluxed to the front end of the selective catalytic dehydrogenation unit. After selective catalytic dehydrogenation treatment, the green oxygen continues to enter the post-reaction dehydration unit to remove the water generated during the dehydrogenation reaction. When the detected particulate matter content does not meet the set requirements, it is returned to the front end of the precision filter unit; When two or more indicators are detected as not meeting the set requirements, the flow is returned to the inlet of the green oxygen purification module or the front end of the corresponding non-compliant indicator processing unit.

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