A method for improving the quality of decarbonized gas

Abstract

The present application belongs to the technical field of blast furnace gas purification treatment, and specifically discloses a method for improving the quality of decarburization gas, comprising the following steps: firstly, detecting the key indicators of the decarburization gas and analyzing the factors affecting the quality thereof; then, grading the quality of the decarburization gas and dynamically adjusting the purification process parameters; then, establishing a target function with the lowest unit cost of decarburization gas treatment as the target and setting constraint conditions for solving, then adjusting the purification process parameters according to the results; finally, monitoring the indicators of the decarburization gas at the detection points and fine-tuning the process parameters according to the results. In view of the problem that the quality and cost of the current decarburization gas are difficult to coordinate, the present application realizes precise controllability of the quality of the decarburization gas, optimal operation cost, and stable and efficient operation of the system through the grading standard of the quality of the decarburization gas, dynamic process control and multi-stage purification process, solves the problem that the traditional blast furnace decarburization gas is affected by the large fluctuation of CO2 content, incomplete removal of impurities and the difficulty in coordinating the quality and cost, thereby affecting the stable operation of the decarburization system.

Description

Technical Field

[0001] This invention relates to the field of blast furnace gas purification and treatment technology, specifically to a method for improving the quality of decarbonized gas. Background Technology

[0002] Decarbonized gas, as a key auxiliary gas in the 2500HyCROF blast furnace smelting system, is widely used in blast furnace blasting, pulverized coal injection conveying, and furnace sealing. Its CO2 content, purity, and stability directly affect blast furnace smelting efficiency, molten iron quality, energy consumption, and low-carbon operation. Currently, adsorption processes are the mainstream solution for blast furnace gas decarbonization and purification. However, existing technologies generally employ fixed parameter operation and traditional process configurations, which have significant shortcomings in quality control, purification effect, economy, and system stability, making it difficult to meet the high-efficiency, low-carbon, and stable production requirements of modern large-scale blast furnaces.

[0003] Current decarbonization gas treatment technologies suffer from several shortcomings. First, CO2 content control precision is insufficient: affected by fluctuations in blast furnace gas composition, the CO2 content of the decarbonized gas fluctuates between 2.5% and 5.0%, far exceeding the stable range required for production. Excessive CO2 fluctuations reduce the gas's calorific value, weaken combustion efficiency, disrupt the balance of reduction reactions within the furnace, and exacerbate fluctuations in blast furnace operating conditions. Second, the purification process lacks systematic optimization: insufficient pretreatment and post-treatment capabilities result in incomplete removal of impurities such as dust and moisture, easily leading to adsorbent poisoning, agglomeration, and increased pressure drop, reducing CO2 adsorption efficiency. Simultaneously, it causes wear and tear on valves, pipelines, and injection equipment, thus shortening equipment lifespan and increasing maintenance costs. Furthermore, no dynamic adjustment mechanism has been established to address factors such as fluctuations in blast furnace gas composition and changes in equipment operating conditions, causing the purification effect to deteriorate rapidly over time, making it difficult to consistently meet standards. III. Imbalance between Cost and Quality: Simply pursuing decarbonization depth significantly increases adsorbent consumption, regeneration energy consumption, and equipment load, while excessive cost control leads to insufficient decarbonization depth and excessive impurities, creating a contradiction of "quality improvement - cost surge." The lack of a quantitative optimization model that balances quality and cost results in significant operational haphazardness. IV. Lack of a Systematic Evaluation and Optimization Framework: The absence of differentiated quality standards for different operating conditions and levels means that a single set of process parameters is used across normal smelting, capacity expansion, and abnormal furnace conditions, failing to match the dynamic gas demand of the blast furnace. The lack of a database linking quality, process, and cost, along with a continuous optimization mechanism, hinders data support for technology upgrades, parameter adjustments, and maintenance strategies, making it difficult to achieve long-term stable and efficient operation of the decarbonization system and restricting the overall economic efficiency and low-carbon level improvement of the blast furnace.

[0004] In conclusion, it is necessary to design a method to improve the quality of decarbonized gas in order to solve the problem that the traditional blast furnace decarbonized gas has large fluctuations in CO2 content, incomplete removal of impurities, and difficulty in balancing quality and cost, which affects the stable operation of the decarbonization system. Summary of the Invention

[0005] The purpose of this invention is to provide a method for improving the quality of decarbonized gas, so as to solve the problem that the decarbonization gas of traditional blast furnaces is affected by large fluctuations in CO2 content, incomplete removal of impurities, and difficulty in balancing quality and cost, which affects the stable operation of the decarbonization system.

[0006] To achieve the above objectives, the basic solution provided by this invention is: a method for improving the quality of decarbonized gas, comprising the following steps: S1: First, the key indicators of decarbonized gas are tested, and the impact of blast furnace gas composition, purification process parameters, and equipment operating status on the quality of decarbonized gas is analyzed in combination with the test data. S2: Next, the quality of the decarburized gas is classified according to the blast furnace smelting requirements. Then, the adsorption process parameters and regeneration process parameters are dynamically adjusted based on the analysis results in S1 and the decarburized gas quality classification standards. S3: Then, with the goal of minimizing the unit cost of decarbonized gas treatment, an objective function is established and constraints are set. Then, combined with the constraints, a genetic algorithm is used to solve the objective function, and the purification process parameters are adjusted according to the results. S4: Finally, monitor the CO2, O2, dust, and moisture content, as well as the adsorption pressure and adsorption temperature of the decarbonized gas at the blast furnace gas inlet, blast furnace gas pretreatment stage, adsorption tower inlet and outlet, and blast furnace gas inlet every 2 minutes, and fine-tune the process parameters based on the monitoring data to stabilize the quality of the decarbonized gas.

[0007] The beneficial effects of the present invention are as follows: (1) The present invention uses a decarbonization gas quality grading standard, dynamic process control and multi-stage purification process to stably control the CO2 content in the decarbonization gas at 1.5-2.0% with a fluctuation range of ≤±0.2%, and reduces the dust and moisture content in the decarbonization gas to ≤8mg / Nm³ respectively. 3 ≤4g / Nm 3 (1) It can adapt to the gas demand of different working conditions of blast furnace, and greatly improve the smelting stability and combustion efficiency; (2) By establishing a cost adaptation optimization model and using genetic algorithm to solve the optimal parameters, under the premise of ensuring quality standards, the unit treatment cost of decarbonized gas is reduced by 12-15%, the adsorbent consumption cost is reduced by 18%, and the regeneration energy consumption cost is reduced by 14%, which solves the contradiction of cost surge due to the improvement of decarbonized gas quality and achieves a win-win situation of economic and technical benefits; (3) The whole process is monitored online, automatically controlled and closed-loop for fault warning. The equipment fault warning accuracy rate is ≥95%, the abnormal handling response time is ≤5min, and the continuous operation cycle of the decarbonization system is extended by more than 30%, which reduces the occurrence of abnormal blast furnace working conditions caused by gas quality fluctuations.

[0008] Option 2, an optimized version of the basic option, specifies the key indicators in S1, including CO2 content, dust content, moisture content, O2 content, and pressure fluctuation in the decarbonized gas. These key indicators are collected every 5 minutes and monitored continuously for 72 hours. Clearly defining CO2, dust, moisture, O2, and pressure fluctuation as key indicators provides a reliable basis for subsequent optimization.

[0009] Option 3, an optimized version of the basic option, involves analyzing the impact of blast furnace gas composition on the quality of decarbonized gas in S1. Specifically, this involves collecting data on the contents of CO, CO2, H2, and N2 in the blast furnace gas, analyzing the correlation between fluctuations in blast furnace gas composition and the CO2 content in the decarbonized gas, and determining that for every 1% fluctuation in the CO2 content of the blast furnace gas, the CO2 content in the decarbonized gas fluctuates by 0.3-0.4%. The specific steps for analyzing the impact of purification process parameters on the quality of decarbonized gas are as follows: First, analyze the impact of adsorption tower operating parameters on the quality of decarbonized gas, specifically through single-factor experiments to analyze the adsorption... The effects of adsorption pressure, adsorption temperature, and gas flow rate on CO2 adsorption efficiency were investigated. It was found that when the adsorption pressure was 0.75-0.85 MPa, the adsorption temperature was 25-30℃, and the gas flow rate was 0.8-1.0 m / s, the CO2 adsorption efficiency was ≥90%. The effects of regeneration process parameters on the quality of the decarbonized gas were then analyzed. Specifically, the effects of regeneration temperature, regeneration time, and purge gas flow rate on the adsorbent regeneration efficiency were analyzed. It was found that when the regeneration temperature was 150-160℃, the regeneration time was 3 h, and the purge gas flow rate was 70-80 Nm³, the optimal regeneration efficiency was achieved. 3 At a rate of / h, the adsorbent regeneration rate is ≥95%. The specific operation for analyzing the impact of equipment operating status on the quality of decarbonized gas is as follows: The wear and agglomeration of the adsorbent in the adsorption tower packing layer, the degree of filter element blockage in the filtration device, and the valve sealing performance are checked sequentially. It is found that when the adsorbent wear rate is >15%, the CO2 adsorption efficiency decreases by 10-15%, and when the filter element blockage degree is >30%, the dust removal rate of the decarbonized gas decreases by >20%. Clarifying the correlation between component fluctuations provides data support for dynamic control and quantifies the impact of equipment deterioration, facilitating early prediction and maintenance.

[0010] Option 4, the preferred option of the basic scheme, classifies the decarbonized gas quality into three levels in S2. The first-level decarbonized gas quality standard is as follows: under the condition of increased production capacity, the CO2 content in the decarbonized gas is 1.5-1.7%, and the dust content is ≤6mg / Nm³. 3 The quality standard for secondary decarbonization gas is as follows: under normal smelting conditions, the CO2 content in the decarbonization gas is 1.7-1.9%, and the dust content is ≤8mg / Nm³. 3 The moisture content in both the primary and secondary decarbonization gases is ≤4 g / Nm³. 3The O2 content is ≤0.4%, and the pressure fluctuation is ≤±0.015MPa; the quality standard for the third-level decarbonization gas is: under abnormal furnace conditions, the CO2 content in the decarbonization gas is 1.9-2.0%, and the dust content is ≤10mg / Nm³. 3 The grading standards are tailored to the actual gas requirements of blast furnaces, ensuring both high quality of decarbonized gas and economic efficiency, avoiding cost waste or unstable furnace conditions caused by a one-size-fits-all approach.

[0011] Option 5, the preferred option of the basic option, involves adjusting the adsorption process parameters in S2 as follows: First, based on the fluctuation of CO2 content in the blast furnace gas, a dynamic adjustment model for adsorption pressure, P=P, is established. O +0.1×ΔC, where P is the adjusted adsorption pressure, P O Let ΔC be the reference pressure and ΔC be the deviation of the CO2 content in the blast furnace gas from the average value. When the CO2 content in the blast furnace gas increases by 1%, the adsorption pressure is increased by 0.1 MPa. Then, the adsorption temperature is controlled at 25-30℃, and a thermostat is used to ensure that the temperature fluctuation is ≤±1℃. Next, the airflow velocity is adjusted according to the pressure difference between the inlet and outlet of the adsorption tower. When the pressure difference is >0.05 MPa, the airflow velocity is decreased by 0.1 m / s; when the pressure difference is <0.02 MPa, the airflow velocity is increased by 0.05 m / s. The pressure automatically adapts to changes in the CO2 content in the blast furnace gas, making CO2 adsorption more stable. Temperature fluctuations are controlled to ≤±1℃, ensuring adsorption efficiency. Simultaneously, the airflow velocity changes with the pressure difference to avoid insufficient adsorption or low adsorption efficiency.

[0012] Option 6, an optimized version of the basic option, involves adjusting the regeneration process parameters in S2 as follows: First, during the heating phase, the regeneration temperature is raised from room temperature to 150℃; during the isothermal phase, the regeneration temperature is maintained at 150-160℃; and during the cooling phase, the regeneration temperature is lowered to ≤40℃. Then, based on the adsorbent's adsorption capacity decay, i.e., the change in CO2 content in the decarbonized gas, the adsorbent regeneration cycle is adjusted. When the CO2 content in the decarbonized gas approaches 2.0%, the adsorbent regeneration cycle is shortened to 6 hours; when the CO2 content in the decarbonized gas stabilizes at 1.5-1.7%, the adsorbent regeneration cycle is extended to 10 hours. This three-stage temperature control ensures more thorough adsorbent regeneration with lower energy consumption. Simultaneously, the flexible adjustment of the adsorbent regeneration cycle reduces ineffective regeneration, lowering energy consumption and adsorbent loss.

[0013] Option 7 is the preferred option of the basic option. In S3, the constraints include quality constraints, process constraints, and equipment constraints. Specifically, the quality constraints are: CO2 content in the decarbonization gas ∈ [1.5%, 2.0%] and dust content ≤ 8 mg / Nm³. 3 Moisture content ≤ 4g / Nm 3The specific process constraints are: adsorption pressure ∈ [0.7MPa, 0.9MPa], adsorption temperature ∈ [25℃, 30℃], airflow velocity ∈ [0.8m / s, 1.0m / s], and regeneration temperature ∈ [150℃, 160℃]. The specific equipment constraints are: adsorbent wear rate ≤15%, filter element clogging degree ≤30%, and equipment operating load ∈ [70%, 110%]. These comprehensive and rigorous constraints ensure that the solved parameters meet quality requirements, protect the equipment, and comply with process safety standards, avoiding the risks associated with extreme parameters.

[0014] Option 8, an optimal choice of Option 7, yields the following optimal purification process parameters in S3: Under the first-stage decarbonized gas quality, the optimal purification process parameters are: adsorption pressure 0.85 MPa, adsorption temperature 26℃, airflow velocity 0.85 m / s, regeneration temperature 158℃, and adsorbent regeneration cycle 6 h; under the second-stage decarbonized gas quality, the optimal purification process parameters are: adsorption pressure 0.8 MPa, adsorption temperature 28℃, airflow velocity 0.9 m / s, regeneration temperature 155℃, and adsorbent regeneration cycle 8 h; and under the third-stage decarbonized gas quality, the optimal purification process parameters are: adsorption pressure 0.75 MPa, adsorption temperature 30℃, airflow velocity 1.0 m / s, regeneration temperature 152℃, and adsorbent regeneration cycle 10 h.

[0015] Option 9, an optimal choice from the basic option, involves adjusting the adsorption pressure in S4 when the CO2 content in the decarbonized gas is >1.9%, either by increasing the adsorption pressure by 0.05 MPa or shortening the adsorbent regeneration cycle by 1 hour; and adjusting the adsorption pressure when the dust content in the decarbonized gas is >7 mg / Nm³. 3 If the filter element is backflushed at a pressure of 0.6 MPa using a purging device for 30 seconds, and the dust content in the decarbonized gas does not decrease after purging the filter element, a filter element replacement warning will be issued. If the adsorption pressure fluctuation is greater than ±0.015 MPa, the frequency of the gas delivery pump will be adjusted. Detailed Implementation

[0016] The present invention will be further described in detail below through specific embodiments: Example A method for improving the quality of decarbonized gas includes the following steps: S1: First, the blast furnace gas undergoes dust removal and dehydration treatment to ensure that the dust content in the blast furnace gas is ≤5mg / Nm³. 3 Moisture content ≤3g / Nm 3This reduces the processing load on the adsorption tower. The pretreated blast furnace gas is then transported to the adsorption tower, where a high-efficiency composite adsorbent adsorbs CO2, and alumina adsorbs moisture. The high-efficiency composite adsorbent consists of activated carbon and molecular sieves, with a molecular sieve to activated carbon mass ratio of 7:3. The high-efficiency composite adsorbent has a CO2 adsorption capacity ≥20 mg / g, an adsorption selectivity (CO2 / N2) ≥100, and an attenuation rate ≤5%. S2: Next, the CO2 content, dust content, moisture content, O2 content, and pressure fluctuation index in the decarbonization gas are collected every 5 minutes by online gas analyzers, dust concentration detectors, and dew point meters at key nodes of the decarbonization system outlet, blast furnace blast inlet, and pulverized coal conveying pipeline. This is monitored continuously for 72 hours. Then, the impact of blast furnace gas composition, purification process parameters, equipment operating status, and cost-related factors on the quality of decarbonization gas is analyzed based on the collected data. The specific procedures for analyzing the impact of blast furnace gas composition on the quality of decarbonized gas are as follows: The contents of CO, CO2, H2, and N2 in the blast furnace gas are collected, and the correlation between fluctuations in blast furnace gas composition and CO2 content in the decarbonized gas is analyzed. It is found that for every 1% fluctuation in CO2 content in the blast furnace gas, the CO2 content in the decarbonized gas fluctuates by 0.3-0.4%. The specific procedures for analyzing the impact of purification process parameters on the quality of decarbonized gas are as follows: First, the impact of adsorption tower operating parameters on the quality of decarbonized gas is analyzed. Specifically, single-factor experiments are conducted to analyze the adsorption pressure, adsorption... The effects of temperature and gas flow rate on CO2 adsorption efficiency were investigated, revealing that the CO2 adsorption efficiency was ≥90% when the adsorption pressure was 0.75-0.85 MPa, the adsorption temperature was 25-30℃, and the gas flow rate was 0.8-1.0 m / s. The influence of regeneration process parameters on the quality of the decarbonized gas was then analyzed, specifically the effects of regeneration temperature, regeneration time, and purge gas flow rate on the adsorbent regeneration efficiency. The results showed that the optimal regeneration temperature was 150-160℃, the regeneration time was 3 h, and the purge gas flow rate was 70-80 Nm³. 3 At a rate of / h, the adsorbent regeneration rate is ≥95%. The specific operation for analyzing the impact of equipment operating status on the quality of decarbonized gas is as follows: The wear and agglomeration of the adsorbent in the adsorption tower packing layer, the degree of filter element blockage in the filter device, and the valve sealing performance are checked sequentially. It is found that when the adsorbent wear rate is >15%, the CO2 adsorption efficiency decreases by 10-15%, and when the filter element blockage degree is >30%, the dust removal rate of the decarbonized gas decreases by >20%. The key factors influencing the cost of decarbonized gas treatment are analyzed: adsorbent consumption costs account for 45%, regeneration energy consumption costs account for 30%, equipment maintenance costs account for 15%, and labor costs account for 10%. Therefore, it is concluded that for every 0.1 MPa increase in adsorption pressure, energy consumption costs increase by 8-10%, and for every 10°C increase in regeneration temperature, energy consumption costs increase by 5-7%. S3: Next, based on the blast furnace smelting requirements, the quality of decarburized gas is divided into three grades. The quality standard for Grade 1 decarburized gas is: under capacity expansion conditions, the CO2 content in the decarburized gas is 1.5-1.7%, and the dust content is ≤6mg / Nm³. 3 Moisture content ≤ 4g / Nm 3 The O2 content should be ≤0.4%, and the pressure fluctuation should be ≤±0.015MPa. The quality standard for secondary decarbonization gas is: under normal smelting conditions, the CO2 content in the decarbonization gas should be 1.7-1.9%, and the dust content ≤8mg / Nm³. 3 Moisture content ≤ 4g / Nm 3 The O2 content should be ≤0.4%, and the pressure fluctuation should be ≤±0.015MPa. The quality standard for the third-level decarbonization gas is: under abnormal furnace conditions, the CO2 content in the decarbonization gas should be 1.9-2.0%, and the dust content ≤10mg / Nm³. 3 ; Subsequently, based on the analysis results in S1 and the decarbonization gas quality grading standards, the adsorption process parameters were adjusted. Specifically, firstly, based on the fluctuations in CO2 content in the blast furnace gas, a dynamic adjustment model for adsorption pressure, P=P, was established. O +0.1×ΔC, where P is the adjusted adsorption pressure (MPa), P O The reference pressure is 0.8 MPa, and ΔC is the deviation (%) of the CO2 content in the blast furnace gas from the mean. When the CO2 content in the blast furnace gas increases by 1%, the adsorption pressure is increased by 0.1 MPa to ensure stable CO2 adsorption efficiency. Then, the adsorption temperature is controlled at 25-30℃ and the temperature is kept within ±1℃ by a constant temperature device. Then, the airflow velocity is adjusted according to the pressure difference between the inlet and outlet of the adsorption tower. When the pressure difference is >0.05 MPa, the airflow velocity is reduced by 0.1 m / s to avoid insufficient adsorption due to excessive flow rate. When the pressure difference is <0.02 MPa, the airflow velocity is increased by 0.05 m / s to improve CO2 adsorption efficiency. Simultaneously, the regeneration process parameters are adjusted as follows: during the heating stage, the regeneration temperature is raised from room temperature to 150℃; during the isothermal stage, the regeneration temperature is maintained at 150-160℃; and during the cooling stage, the regeneration temperature is reduced to ≤40℃. This ensures thorough adsorbent regeneration and optimal energy consumption. Then, based on the adsorbent's adsorption capacity decay, i.e., the change in CO2 content in the decarbonized gas, the adsorbent regeneration cycle is adjusted. Under normal operating conditions, the adsorbent regeneration cycle is 8 hours. When the CO2 content in the decarbonized gas approaches 2.0%, the adsorbent regeneration cycle is shortened to 6 hours. When the CO2 content in the decarbonized gas stabilizes at 1.5-1.7%, the adsorbent regeneration cycle is extended to 10 hours to reduce regeneration energy consumption. Finally, a dust removal device is used to filter the dust in the decarbonized gas. The filter element of the dust removal device has a precision of 0.5μm. S4: Then, with the goal of minimizing the unit cost of decarbonized gas treatment, establish the objective function Min C = αC1 + βC2 + γC3 + δC4 and set constraints, where Min C is the unit treatment cost (yuan / Nm). 3 C1 represents adsorbent consumption cost, C2 represents regeneration energy cost, C3 represents equipment maintenance cost, and C4 represents labor cost. α, β, γ, and δ are weighting coefficients (here, α=0.45, β=0.30, γ=0.15, and δ=0.10 based on actual data). Constraints include quality constraints, process constraints, and equipment constraints. Specifically, the quality constraints are: CO2 content in the decarbonized gas ∈ [1.5%, 2.0%] and dust content ≤ 8 mg / Nm³. 3 Moisture content ≤ 4g / Nm 3 The specific process constraints are: adsorption pressure ∈ [0.7MPa, 0.9MPa], adsorption temperature ∈ [25℃, 30℃], airflow velocity ∈ [0.8m / s, 1.0m / s], and regeneration temperature ∈ [150℃, 160℃]. The specific equipment constraints are: adsorbent wear rate ≤15%, filter element clogging degree ≤30%, and equipment operating load ∈ [70%, 110%]. Then, combining the constraints of quality, process, and equipment, a genetic algorithm is used to solve the objective function, yielding the optimal purification process parameters for the first-stage decarbonized gas quality: adsorption pressure 0.85MPa, adsorption temperature 26℃, airflow velocity 0.85m / s, regeneration temperature 158℃, and adsorbent regeneration cycle 6h. Based on these parameters, the unit cost of purifying the blast furnace gas and ultimately treating the decarbonized gas is 0.098 yuan / Nm³. 3 The optimal purification process parameters for the secondary decarbonized gas quality are: adsorption pressure of 0.8 MPa, adsorption temperature of 28℃, airflow velocity of 0.9 m / s, regeneration temperature of 155℃, and adsorbent regeneration cycle of 8 hours. Under these conditions, the minimum unit cost for decarbonized gas treatment is 0.085 yuan / Nm³. 3 The optimal purification process parameters for the three-stage decarbonized gas quality are: adsorption pressure of 0.75 MPa, adsorption temperature of 30℃, airflow velocity of 1.0 m / s, regeneration temperature of 152℃, and adsorbent regeneration cycle of 10 h. Under these conditions, the minimum unit cost for decarbonized gas treatment is 0.078 yuan / Nm³. 3 ; Next, the purification process parameters are fine-tuned based on raw material price fluctuations and the above results: when the adsorbent price increases by ≥10%, the adsorbent regeneration cycle is extended by 1-2 hours to reduce the frequency of adsorbent replacement; when electricity prices are at their lowest, the adsorption pressure and regeneration temperature are appropriately increased to improve the quality of the decarbonized gas; the purification process parameters are fine-tuned based on the blast furnace operating conditions: when blast furnace capacity increases, costs may increase by 5-8% while ensuring quality standards are met; when the blast furnace is in abnormal conditions, the process parameters are optimized to reduce costs while meeting the minimum quality requirements of the decarbonized gas, such as extending the adsorbent regeneration cycle to 10 hours to reduce energy consumption costs; the purification process parameters are fine-tuned based on equipment status: during equipment maintenance, the adsorption pressure is reduced to 0.7MPa to reduce energy consumption, and a backup adsorption tower is activated to ensure that the quality of the decarbonized gas is not lower than the third-level standard; S5: Then, monitor the CO2, O2, dust, and moisture content, as well as the adsorption pressure and temperature, of the decarbonized gas at the blast furnace gas inlet, blast furnace gas pretreatment stage, adsorption tower inlet and outlet, and blast furnace gas inlet every 2 minutes. When the CO2 content in the decarbonized gas is >1.9%, increase the adsorption pressure by 0.05 MPa or shorten the adsorbent regeneration cycle by 1 hour. When the dust content in the decarbonized gas is >7 mg / Nm³, increase the adsorption pressure by 0.05 MPa or shorten the adsorbent regeneration cycle by 1 hour. 3 If the dust content in the decarbonized gas does not decrease after purging, a filter element replacement warning is issued. If the adsorption pressure fluctuation is greater than ±0.015MPa, the gas delivery pump frequency is adjusted to stabilize the pressure. If the adsorbent wear rate is greater than 12% and the filter element blockage is greater than 25%, an equipment maintenance warning is triggered. If the CO2 content in the decarbonized gas is greater than 2.0% for 30 minutes, an emergency response procedure is initiated to switch the adsorption tower to the standby adsorption tower to ensure that the blast furnace gas supply is not affected. Finally, regular equipment maintenance is carried out, specifically: daily checks on the accuracy of monitoring equipment data, valve opening and closing status, gas leaks, and cleaning of dust accumulation in the pretreatment unit; weekly checks on the inlet and outlet pressure difference of the adsorption tower and the height of the adsorbent bed to assess wear and clean the filter elements and filter housings; every 3 months, replacement of adsorbent with a wear rate >15%, replacement of the top 30% of the adsorbent in the adsorption tower, and comprehensive calibration of the online monitoring equipment while checking the condition of the internal anti-corrosion layer of the adsorption tower; and annual comprehensive overhaul of the adsorption tower, regeneration unit, and conveying pipelines, including replacement of all filter elements and aging valves.

[0017] In summary, this integrated approach, encompassing key indicator detection and diagnosis, dynamic parameter adjustment, cost model optimization, and real-time monitoring throughout the entire process, not only ensures that key indicators such as CO2, dust, moisture, and O2 in the decarbonized gas consistently meet standards, but also flexibly matches graded quality requirements according to different blast furnace smelting conditions. Simultaneously, it effectively controls adsorbent consumption and regeneration energy consumption, preventing unreasonable cost increases. Through dynamic adaptation of adsorption and regeneration processes, genetic algorithm optimization, automatic backflushing, and closed-loop parameter adjustment, precise and controllable decarbonized gas quality, optimal operating costs, and stable and efficient system operation are achieved. Ultimately, the CO2 content in the decarbonized gas is stably controlled at 1.5%-2.0%, operating costs are reduced by 12-15%, and the continuous operating cycle of the system is extended by more than 30%, effectively improving the blast furnace smelting efficiency and economy.

[0018] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for improving the quality of decarbonized gas, characterized in that, Includes the following steps: S1: First, the key indicators of decarbonized gas are tested, and the impact of blast furnace gas composition, purification process parameters, and equipment operating status on the quality of decarbonized gas is analyzed in combination with the test data. S2: Next, the quality of the decarburized gas is classified according to the blast furnace smelting requirements. Then, the adsorption process parameters and regeneration process parameters are dynamically adjusted based on the analysis results in S1 and the decarburized gas quality classification standards. S3: Then, with the goal of minimizing the unit cost of decarbonized gas treatment, an objective function is established and constraints are set. Then, combined with the constraints, a genetic algorithm is used to solve the objective function, and the purification process parameters are adjusted according to the results. S4: Finally, monitor the CO2, O2, dust, and moisture content, as well as the adsorption pressure and adsorption temperature of the decarbonized gas at the blast furnace gas inlet, blast furnace gas pretreatment stage, adsorption tower inlet and outlet, and blast furnace gas inlet every 2 minutes, and fine-tune the process parameters based on the monitoring data to stabilize the quality of the decarbonized gas.

2. The method for improving the quality of decarbonized gas according to claim 1, characterized in that, In S1, the key indicators include the CO2 content, dust content, moisture content, O2 content, and pressure fluctuation of the decarbonized gas; the key indicators of the decarbonized gas are collected every 5 minutes and continuously monitored for 72 hours.

3. The method for improving the quality of decarbonized gas according to claim 1, characterized in that, In S1, the specific operation for analyzing the impact of blast furnace gas composition on the quality of decarbonized gas is as follows: The contents of CO, CO2, H2, and N2 in the blast furnace gas are collected, and the correlation between fluctuations in blast furnace gas composition and CO2 content in the decarbonized gas is analyzed. It is found that for every 1% fluctuation in CO2 content in the blast furnace gas, the CO2 content in the decarbonized gas fluctuates by 0.3-0.4%. The specific operation for analyzing the impact of purification process parameters on the quality of decarbonized gas is as follows: First, the impact of adsorption tower operating parameters on the quality of decarbonized gas is analyzed, specifically through single-factor experiments analyzing the adsorption pressure of the adsorption tower, ... The effects of adsorption temperature and gas flow rate on CO2 adsorption efficiency were investigated, revealing that the CO2 adsorption efficiency was ≥90% when the adsorption pressure was 0.75-0.85 MPa, the adsorption temperature was 25-30℃, and the gas flow rate was 0.8-1.0 m / s. The influence of regeneration process parameters on the quality of the decarbonized gas was then analyzed, specifically the effects of regeneration temperature, regeneration time, and purge gas flow rate on the adsorbent regeneration efficiency. The results showed that the optimal regeneration temperature was 150-160℃, the regeneration time was 3 h, and the purge gas flow rate was 70-80 Nm³. 3 At a rate of / h, the adsorbent regeneration rate is ≥95%; the specific operation to analyze the impact of equipment operation status on the quality of decarbonized gas is as follows: check the wear and agglomeration of adsorbent in the packing layer of the adsorption tower, the degree of filter element blockage in the filter device, and the valve sealing performance in sequence. It is found that when the adsorbent wear rate is >15%, the CO2 adsorption efficiency decreases by 10-15%, and when the filter element blockage degree is >30%, the dust removal rate of decarbonized gas decreases by >20%.

4. The method for improving the quality of decarbonized gas according to claim 1, characterized in that, In S2, the quality of decarbonized gas is divided into three levels. The first-level decarbonized gas quality standard is as follows: under the condition of increased production capacity, the CO2 content in the decarbonized gas is 1.5-1.7%, and the dust content is ≤6mg / Nm³. 3 The quality standard for secondary decarbonization gas is as follows: under normal smelting conditions, the CO2 content in the decarbonization gas is 1.7-1.9%, and the dust content is ≤8mg / Nm³. 3 The moisture content in both the primary and secondary decarbonization gases is ≤4 g / Nm³. 3 The O2 content is ≤0.4%, and the pressure fluctuation is ≤±0.015MPa; the quality standard for the third-level decarbonization gas is: under abnormal furnace conditions, the CO2 content in the decarbonization gas is 1.9-2.0%, and the dust content is ≤10mg / Nm³. 3 .

5. The method for improving the quality of decarbonized gas according to claim 1, characterized in that, In S2, the specific method for adjusting the adsorption process parameters is as follows: First, based on the fluctuation of CO2 content in the blast furnace gas, establish a dynamic adjustment model for adsorption pressure P=P O +0.1×ΔC, where P is the adjusted adsorption pressure, P0 O Let ΔC be the reference pressure and ΔC be the deviation of the CO2 content in the blast furnace gas from the average value. When the CO2 content in the blast furnace gas increases by 1%, the adsorption pressure is increased by 0.1 MPa. Then, the adsorption temperature is controlled at 25-30℃ and the temperature is kept constant to ensure that the adsorption temperature fluctuation is ≤±1℃. Then, the airflow velocity is adjusted according to the pressure difference between the inlet and outlet of the adsorption tower. When the pressure difference is >0.05 MPa, the airflow velocity is decreased by 0.1 m / s; when the pressure difference is <0.02 MPa, the airflow velocity is increased by 0.05 m / s.

6. The method for improving the quality of decarbonized gas according to claim 1, characterized in that, In S2, the specific method for adjusting the regeneration process parameters is as follows: First, during the heating stage, the regeneration temperature is raised from room temperature to 150℃; during the constant temperature stage, the regeneration temperature is maintained at 150-160℃; and during the cooling stage, the regeneration temperature is reduced to ≤40℃. Then, based on the attenuation of the adsorbent's adsorption capacity, i.e., the change in CO2 content in the decarbonized gas, the adsorbent regeneration cycle is adjusted. When the CO2 content in the decarbonized gas is close to 2.0%, the adsorbent regeneration cycle is shortened to 6 hours; when the CO2 content in the decarbonized gas stabilizes at 1.5-1.7%, the adsorbent regeneration cycle is extended to 10 hours.

7. The method for improving the quality of decarbonized gas according to claim 1, characterized in that, In S3, the constraints include quality constraints, process constraints, and equipment constraints. Specifically, the quality constraints are: CO2 content in the decarbonized gas ∈ [1.5%, 2.0%] and dust content ≤ 8 mg / Nm³. 3 Moisture content ≤ 4g / Nm 3 The specific process constraints are: adsorption pressure ∈ [0.7MPa, 0.9MPa], adsorption temperature ∈ [25℃, 30℃], airflow velocity ∈ [0.8m / s, 1.0m / s], and regeneration temperature ∈ [150℃, 160℃]. The specific equipment constraints are: adsorbent wear rate ≤15%, filter element clogging degree ≤30%, and equipment operating load ∈ [70%, 110%].

8. A method for improving the quality of decarbonized gas according to claim 7, characterized in that, In S3, solving the objective function yields the optimal purification process parameters for the first-stage decarbonized gas quality as follows: adsorption pressure 0.85 MPa, adsorption temperature 26℃, airflow velocity 0.85 m / s, regeneration temperature 158℃, and adsorbent regeneration cycle 6 h; the optimal purification process parameters for the second-stage decarbonized gas quality are: adsorption pressure 0.8 MPa, adsorption temperature 28℃, airflow velocity 0.9 m / s, regeneration temperature 155℃, and adsorbent regeneration cycle 8 h; and the optimal purification process parameters for the third-stage decarbonized gas quality are: adsorption pressure 0.75 MPa, adsorption temperature 30℃, airflow velocity 1.0 m / s, regeneration temperature 152℃, and adsorbent regeneration cycle 10 h.

9. A method for improving the quality of decarbonized gas according to claim 1, characterized in that, In S4, when the CO2 content in the decarbonized gas is >1.9%, the adsorption pressure is increased by 0.05 MPa or the adsorbent regeneration cycle is shortened by 1 hour; when the dust content in the decarbonized gas is >7 mg / Nm³, the adsorption pressure is increased by 0.05 MPa or the adsorbent regeneration cycle is shortened by 1 hour. 3 If the filter element is backflushed at a pressure of 0.6 MPa using a purging device for 30 seconds, and the dust content in the decarbonized gas does not decrease after purging the filter element, a filter element replacement warning will be issued. If the adsorption pressure fluctuation is greater than ±0.015 MPa, the frequency of the gas delivery pump will be adjusted.