Control method for circulation parameters of hydrogen-rich carbon circulation oxygen blast furnace decarburization system

Abstract

The invention belongs to the technical field of blast furnace ironmaking, and particularly discloses a control method for circulation parameters of a hydrogen-rich carbon circulation oxygen blast furnace decarburization system, which comprises the following steps: firstly, inputting known circulation parameters into an operation module of the decarburization system, calculating theoretical amine liquid circulation volume, and when the actual amine liquid circulation volume is greater than the theoretical amine liquid circulation volume by 100m < 3 > / h, determining that the actual amine liquid circulation volume is smaller than 100m < 3 > / h; and adjusting the actual amine liquid circulation volume of the decarburization system into the theoretical amine liquid circulation volume output by the output module. The problems that in the actual operation process of a decarburization system, the amine liquid circulation amount, the content of effective carbon dioxide in feed gas and the carbon dioxide amount of target decarburization coal gas are not matched in operation, so that the operation efficiency is low, and energy consumption is high are solved. According to the method, the theoretical amine liquid circulation volume matched with the current decarbonization system is calculated through the known circulation parameters, adjustment is carried out according to the comparison of the actual amine liquid circulation volume and the theoretical value, it is ensured that the decarbonization process can be efficiently and stably carried out, and therefore the operation efficiency of the whole decarbonization system is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of blast furnace ironmaking, and particularly to a control method for circulation parameters of a decarbonization system in a hydrogen-rich carbon cycle oxygen blast furnace. Background Art

[0002] The hydrogen-rich carbon cycle oxygen blast furnace (HyCROF) is different from the traditional blast furnace smelting process. It abandons the way of blowing air for heating and instead uses oxygen blowing. In the operation of the hydrogen-rich carbon cycle oxygen blast furnace, the link of heating and recycling the top gas after removing carbon dioxide is particularly ingenious, effectively reducing carbon dioxide emissions and realizing low-carbon metallurgy. According to actual operation data, this process can reduce the fossil energy consumption in the ironmaking process by more than 35%, and at the same time reduce the process carbon emissions by about 30%, which has a milestone significance for the development of the steel industry towards low carbon.

[0003] In the hydrogen-rich carbon cycle oxygen blast furnace system, the decarbonization system plays a key role and is the core part for realizing carbon dioxide removal. At present, the most widely used in the decarbonization system is the MDEA solution (hereinafter referred to as amine solution). Under specific working conditions of high pressure and low temperature, the amine solution can efficiently absorb carbon dioxide in the top gas. Physical and chemical interactions occur between amine solution molecules and carbon dioxide molecules to separate carbon dioxide from the gas to form a rich liquid rich in carbon dioxide. Under the conditions of low pressure and high temperature, the carbon dioxide in the rich liquid will be released, enabling the amine solution to be regenerated and become lean liquid again, and then can be reused. This way of recycling not only ensures the continuous and stable operation of the decarbonization system, but also reduces costs and resource consumption to a certain extent.

[0004] However, in the actual operation process of the decarbonization system, due to the mismatch in the circulation volume of the amine solution, the content of effective carbon dioxide in the raw gas, and the carbon dioxide amount of the target decarbonized gas, the balance of the entire system is affected, resulting in low operation efficiency and high energy consumption of the decarbonization system. Summary of the Invention

[0005] The purpose of the present invention is to provide a control method for circulation parameters of a decarbonization system in a hydrogen-rich carbon cycle oxygen blast furnace to solve the problem that in the actual operation process of the decarbonization system, the circulation volume of the amine solution, the content of effective carbon dioxide in the raw gas, and the carbon dioxide amount of the target decarbonized gas are mismatched, resulting in low operation efficiency and high energy consumption of the decarbonization system.

[0006] To achieve the above object, the basic solution provided by the present invention is: A control method for circulation parameters of a decarbonization system in a hydrogen-rich carbon cycle oxygen blast furnace, including the following steps:

[0007] S1. First, input known cycle parameters at the input end of the operation module in the decarbonization control system, and calculate the theoretical amine solution circulation rate through the calculation formula in the operation module;

[0008] S2. After calculating the theoretical amine solution circulation rate, output it to the operation interface through the output module of the decarbonization system;

[0009] S3. When the difference between the actual amine solution circulation rate and the theoretical amine solution circulation rate is greater than 100 m 3 / h, adjust the actual amine solution circulation rate of the decarbonization system to the theoretical amine solution circulation rate. When the difference between the actual amine solution circulation rate and the theoretical amine solution circulation rate is less than or equal to 100 m 3 / h, then do not adjust the actual amine solution circulation rate.

[0010] The beneficial effects of the present invention are as follows: By calculating the theoretical amine solution circulation rate matching the current decarbonization system through known cycle parameters and making adjustments based on the comparison between the actual amine solution circulation rate and the theoretical value, it is possible to avoid the problem of low operation efficiency of the decarbonization system caused by the mismatch of actual cycle parameters during operation, ensure that the decarbonization process can proceed efficiently and stably, and thus improve the operation efficiency of the entire decarbonization system. When the operation efficiency of the decarbonization system is improved, correspondingly, the additional energy consumption generated due to low operation efficiency can be reduced, and the unnecessary energy consumption caused by unreasonable amine solution circulation rate and other factors can be avoided, achieving the most economical operation effect.

[0011] Solution two, which is the optimization of the basic solution. The known cycle parameters include the outlet flow rate of the gas compressor, the CO2 content of the raw gas, the residual CO2 content of the decarbonized gas, the amount of decarbonized gas after purification, the rich amine solution temperature, and the lean amine solution temperature.

[0012] Solution three, which is the optimization of the basic solution. In S1, the calculation formula of the operation module in the decarbonization control system is as follows:

[0013]

[0014] In the formula: L 理论 —Theoretical amine solution circulation rate; Q1—the outlet flow rate of the gas compressor; C1—the CO2 content of the raw gas; Q2—the amount of decarbonized gas after purification; C2—the residual CO2 content of the decarbonized gas; T1—the rich amine solution temperature; T2—the lean amine solution temperature; the above Q1, Q2, C1, C2, T1, and T2 are all actual production values; μ—the specific heat capacity of the decarbonization solution; θ—the molar chemical reaction heat of the amine solution; V—the molar volume of the gas, with a value of 22.4 L / mol.

[0015] Solution four, which is the optimization of solution three. The calculation formula of the molar chemical reaction heat θ of the amine solution is as follows:

[0016]

[0017] In the formula: θ is the molar chemical reaction heat of the amine solution; L is the actual amine solution circulation volume; T1 is the rich amine solution temperature; T2 is the lean amine solution temperature; the above M, L, T1, and T2 are all actual production values; μ is the specific heat capacity of the decarbonization solution; V is the molar volume of the gas, with a value of 22.4 L / mol; M is the total carbon dioxide absorption amount.

[0018] Solution Five, which is the optimization of Solution Four. When the theoretical amine solution circulation volume is calculated, if the difference between the actual amine solution circulation volume and the theoretical amine solution circulation volume is greater than 100 m 3 / h, it is necessary to recalculate the molar chemical reaction heat of the amine solution through the known circulation parameters, and then input the recalculated molar chemical reaction heat of the amine solution into the formula for the theoretical amine solution circulation volume as the basis for calculating a new round of theoretical amine solution circulation volume; the amine solution circulation volume is directly related to the operating cost of the process. If the actual circulation volume is too large, it will increase the power consumption of the pump and the regeneration cost of the amine solution, etc. Recalculating the molar chemical reaction heat of the amine solution can make the amine solution circulation volume more reasonable, which can reduce the production cost and improve the economy of the process while ensuring the process effect.

[0019] Solution Six, which is the optimization of Solution Three. The specific heat capacity of the decarbonization solution is taken as 3.4 Mj / kg·°C; during the decarbonization process, the amine solution will convert between the rich liquid and lean liquid states, involving a large amount of heat exchange. The specific heat capacity of the decarbonization solution being 3.4 Mj / kg·°C enables a more accurate value to be obtained when calculating the temperature change between the rich liquid and the lean liquid. Specific Embodiments

[0020] The present invention will be further described in detail below through specific embodiments:

[0021] A control method for the circulation parameters of a decarbonization system in a hydrogen-rich carbon cycle oxygen blast furnace includes the following steps:

[0022] S1. First, input the known circulation parameters at the input end of the decarbonization system operation module. The known circulation parameters include the gas compressor outlet flow rate, the raw gas CO2 content, the decarbonized gas residual CO2 content, the purified decarbonized gas volume, the rich amine solution temperature, and the lean amine solution temperature, and calculate the theoretical amine solution circulation volume. The calculation formula of the operation module in the decarbonization control system is as follows:

[0023]

[0024] In the formula: L 理论—Theoretical amine solution circulation volume; Q1—Outlet flow of gas compressor; C1—CO2 content in raw gas; Q2—Decarbonized gas volume after purification; C2—Residual CO2 content in decarbonized gas; T1—Temperature of rich amine solution; T2—Temperature of lean amine solution; The above Q1, Q2, C1, C2, T1 and T2 are all actual production values; μ—Specific heat capacity of decarbonization solution, with a value of 3.4 Mj / kg·°C; θ—Molar chemical reaction heat of amine solution; V—Molar volume of gas, with a value of 22.4 L / mol;

[0025] The calculation formula for the molar chemical reaction heat θ of the amine solution is as follows:

[0026]

[0027] In the formula: θ—Molar chemical reaction heat of amine solution, L—Actual amine solution circulation volume; T1—Temperature of rich amine solution; T2—Temperature of lean amine solution; The above M, L, T1 and T2 are all actual production values; μ—Specific heat capacity of decarbonization solution, with a value of 3.4 Mj / kg·°C; V—Molar volume of gas, with a value of 22.4 L / mol; M—Total carbon dioxide absorption amount;

[0028] In the actual production process when calculating the molar chemical reaction heat, the actual amine solution circulation volume L takes a value of 2500 kg, the temperature of the rich amine solution T1 takes a value of 77.96 °C, the temperature of the lean amine solution T2 takes a value of 60.26 °C, and the total carbon dioxide absorption amount M takes a value of 80000 mol. Substituting the above values into the formula for calculating the molar chemical reaction heat of the amine solution, we get:

[0029]

[0030] θ = 42.13 Mj / mol·°C

[0031] In the above process of calculating the molar chemical reaction heat, the actual amine solution circulation volume is 2500 kg, the temperature of the rich amine solution is 77.96 °C, the temperature of the lean amine solution is 60.26 °C, and the total carbon dioxide absorption amount of 80000 mol is the average value of the operation data of the decarbonization system in the past six months. Since the above values are more in line with the actual production situation, when calculating the theoretical amine solution circulation volume using the molar chemical reaction heat, the obtained theoretical amine solution circulation volume can make the decarbonization system operate more economically.

[0032] S2. After calculating the theoretical amine solution circulation volume, output it to the operation interface through the output module of the decarbonization system;

[0033] S3. When the difference between the actual amine solution circulation volume and the theoretical amine solution circulation volume is greater than 100 m 3 / h, adjust the actual amine solution circulation volume of the decarbonization system to the theoretical amine solution circulation volume. When the difference between the actual amine solution circulation volume and the theoretical amine solution circulation volume is less than or equal to 100 m 3When it is [specific unit] / h, the actual amine solution circulation volume is not adjusted.

[0034] When the theoretical amine solution circulation volume is calculated, if the difference between the actual amine solution circulation volume and the theoretical amine solution circulation volume is greater than 100 m 3 / h, it is necessary to recalculate the molar chemical reaction heat of the amine solution through the known circulation parameters, and then input the recalculated molar chemical reaction heat of the amine solution into the formula of the theoretical amine solution circulation volume as the basis for calculating a new round of theoretical amine solution circulation volume in the subsequent calculation.

[0035] Input any 6 known circulation parameters among the amine solution circulation volume, the outlet flow of the gas compressor, the CO2 content of the raw gas, the decarbonized gas volume after purification, the residual CO2 content of the decarbonized gas, the rich amine solution temperature, and the lean amine solution temperature at the input end of the operation module in the decarbonization control system, and the theoretical value of another circulation parameter can be calculated through the operation module in the decarbonization control system; calculating the theoretical value of the circulation parameter through the operation module in the decarbonization control system and using it as a guiding parameter for production operation can accurately adjust the amine solution circulation volume, the target carbon dioxide, the decarbonized gas volume, and the amine solution temperature, so as to achieve the goal of efficient and economic operation of the decarbonization system.

[0036] The above are only embodiments of the present invention, and common knowledge such as the specific structure and characteristics known in the solution is not described in detail here. It should be noted that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicability of the patent. The protection scope required by this application should be based on the content of its claims, and the specific implementation manners and the like recorded in the specification can be used to explain the content of the claims.

Claims

1. A method for controlling cycle parameters of a hydrogen-rich carbon cycle oxygen blast furnace decarburization system, characterized in that: The following steps are involved: S1. First, input known circulation parameters into the input end of the operation module in the decarbonization control system, and calculate the theoretical amine liquid circulation amount through the calculation formula in the operation module; S2. After calculating the theoretical amine liquid circulation volume, it is output to the operation interface through the output module of the decarbonization system; S3. When the difference between the actual amine liquid circulation volume and the theoretical amine liquid circulation volume is greater than 100m 3 / h, adjust the actual amine liquid circulation volume of the decarbonization system to the theoretical amine liquid circulation volume. When the difference between the actual amine liquid circulation volume and the theoretical amine liquid circulation volume is less than or equal to 100m 3 / h, the actual amine liquid circulation volume will not be adjusted.

2. The method for controlling the cycle parameters of a hydrogen-rich carbon cycle oxygen blast furnace decarburization system according to claim 1, characterized in that: The known circulation parameters include the outlet flow of the coal gas compressor, the CO2 content of the raw gas, the residual CO2 content of the decarbonized coal gas, the amount of decarbonized coal gas after purification, the rich amine liquid temperature and the lean amine liquid temperature.

3. The method for controlling cycle parameters of a hydrogen-rich carbon cycle oxygen blast furnace decarburization system according to claim 1, characterized in that: In S1, the calculation formula of the operation module in the decarbonization control system is as follows: Where: L 理论 —Theoretical amine liquid circulation volume; Q1—gas compressor outlet flow; C1—CO2 content of raw gas; Q2—decarbonized coal gas volume after purification; C2—residual CO2 content of decarbonized coal gas; T1—rich amine liquid temperature; T2—lean amine liquid temperature; the above Q1, Q2, C1, C2, T1 and T2 are all actual production values; μ—specific heat capacity of decarbonized solution; θ—molar chemical reaction heat of amine liquid; V—gas molar volume, value is 22.4L / mol.

4. A method for controlling cycle parameters of a hydrogen-rich carbon cycle oxygen blast furnace decarburization system according to claim 3, characterized in that: The calculation formula of the molar chemical reaction heat θ of the amine solution is as follows: In the formula: θ is the molar chemical reaction heat of amine solution, L is the actual circulation volume of amine solution; T1 is the temperature of rich amine solution; T2 is the temperature of lean amine solution; the above M, L, T1 and T2 are all actual production values; μ is the specific heat capacity of decarbonization solution; V is the molar volume of gas, which is 22.4L / mol; M is the total carbon dioxide absorption.

5. A method for controlling cycle parameters of a hydrogen-rich carbon cycle oxygen blast furnace decarburization system according to claim 4, characterized in that: After the theoretical amine liquid circulation volume is calculated, if the difference between the actual amine liquid circulation volume and the theoretical amine liquid circulation volume is greater than 100m 3 / h, it is necessary to recalculate the molar chemical reaction heat of the amine liquid through the known circulation parameters, and then enter the recalculated molar chemical reaction heat of the amine liquid into the formula of the theoretical amine liquid circulation volume as the basis for subsequent calculation of a new round of theoretical amine liquid circulation volume.

6. The method for controlling cycle parameters of a hydrogen-rich carbon cycle oxygen blast furnace decarburization system according to claim 3, characterized in that: The specific heat capacity of the decarbonization solution is 3.4 Mj / kg·°C.

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