Method and system for evaluating oxygen use efficiency of slab heating furnace under oxygen-enriched co-combustion process

Abstract

The application provides an oxygen use benefit evaluation method and system for a slab heating furnace under an oxygen-enriched mixed combustion process, and belongs to the technical field of hot-rolled slab processing. The method comprises the following steps: during the oxygen use influencing period of the oxygen-enriched mixed combustion process, first, the coal gas energy-saving amount is calculated according to the adjacent slab discharge interval difference of the oxygen-enriched combustion process and the air combustion process, combined with the unit time heat power; second, the slab output increase is calculated according to the output difference of the two processes; third, the electricity energy-saving amount is calculated according to the electricity consumption of the corresponding fan after the oxygen amount of the oxygen-enriched process is replaced by the air amount; and fourth, the heat loss reduction of the flue gas is calculated according to the inert gas amount reduction of the oxygen-enriched process based on the air combustion process, and the heat energy-saving amount is calculated. The total oxygen-enriched mixed combustion benefit is obtained by summing up the four benefits, and the benefit is positive when the total benefit is greater than the oxygen input cost, negative when the total benefit is less than the oxygen input cost, and zero when the total benefit is equal to the oxygen input cost. The application constructs a standardized oxygen-enriched mixed combustion benefit quantitative evaluation system, and provides a quantitative basis for hot-rolled production planning and scheduling.

Description

Technical Field

[0001] This invention relates to the field of hot-rolled slab processing technology, specifically to a method and system for evaluating the oxygen utilization efficiency of a slab heating furnace under an oxygen-enriched co-firing process. Background Technology

[0002] Oxygen-enriched combustion technology has been gradually applied to the hot-rolled slab processing furnace production process in the metallurgical industry in recent years. Currently, the mainstream application is the implementation of oxygen-enriched combustion in the preheating section of the slab heating furnace. Oxygen-enriched combustion is a commonly used high-efficiency combustion optimization technology in industrial furnaces such as slab heating furnaces in the metallurgical industry. Its core is to introduce a high concentration of oxygen into the conventional combustion air of the furnace to replace part of the ordinary combustion air. By optimizing the combustion reaction conditions inside the furnace, it achieves efficient fuel utilization and improved furnace thermal efficiency. It is also a core technical means for slab heating furnaces to achieve increased production and energy conservation. Compared with conventional pure air combustion, it is a targeted combustion system optimization solution. When implemented under suitable production conditions, this technology can effectively achieve multiple production benefits such as increased production, energy conservation, and oxygen pipeline pressure balance, making it an important technical means for efficient production in heating furnaces.

[0003] However, the industry has not yet formed a clear quantitative judgment standard for the reasonable use strategy of oxygen-enriched co-firing in slab heating furnaces. There is a lack of unified evaluation basis for oxygen use benefits among producers, producers, producers, and oxygen suppliers, resulting in insufficient scientific basis for oxygen use decisions. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a method for evaluating the oxygen utilization efficiency of slab heating furnaces under an oxygen-enriched co-firing process, comprising: During the oxygen-enriched co-firing process, based on the difference between the time interval between adjacent slabs exiting the furnace under the oxygen-enriched co-firing process and the time interval between adjacent slabs exiting the furnace under the air-assisted combustion process, and combined with the heat power per unit time, the gas energy saving corresponding to the oxygen-enriched co-firing process is obtained. During the period of oxygen consumption impact of the oxygen-enriched combustion process, the increase in slab output corresponding to the use of the oxygen-enriched combustion process is obtained based on the difference between the output under the oxygen-enriched combustion process and the output under the air-assisted combustion process. During the oxygen consumption period of the oxygen-enriched combustion process, the corresponding fan power consumption after the oxygen quantity under the oxygen-enriched combustion process is equivalently replaced with the air quantity under the air-assisted combustion process is used to obtain the energy saving corresponding to the oxygen-enriched combustion process. During the oxygen-enriched combustion process, based on the air-assisted combustion process, and taking the reduced amount of inert gas introduced into the air under the oxygen-enriched combustion process as a benchmark, the heat loss of flue gas due to the reduction in the total emission of flue gas is calculated, and the corresponding heat energy saving of the oxygen-enriched combustion process is obtained. The total benefit of using the oxygen-enriched co-firing process is obtained by summing the energy saved by the gas, the increased output of the slab, the energy saved by the electricity, and the energy saved by the heat. If the total benefit is greater than the oxygen input cost of the oxygen-enriched co-firing process, the oxygen-enriched co-firing benefit is positive; if the total benefit is less than the oxygen input cost, the oxygen-enriched co-firing benefit is negative; and if the total benefit is equal to the oxygen input cost, the oxygen-enriched co-firing benefit is zero.

[0005] Furthermore, it also includes: if the oxygen-enriched co-firing benefit is negative or zero, then the critical width of the slab when the oxygen-enriched co-firing benefit is zero is calibrated, and slabs with a width greater than the critical width are subjected to the oxygen-enriched co-firing process, while slabs with a width less than or equal to the critical width are subjected to the air-assisted combustion process.

[0006] Furthermore, the specific time period affected by oxygen use is as follows: let the oxygen supply time be... The oxygen supply was shut off at the following time. The time between the oxygen injection time and the time when the first billet from the oxygen-affected area is produced is The period during which oxygen use affects the system is... arrive .

[0007] Furthermore, the specific calculation method for the energy saving of coal gas corresponding to the oxygen-enriched co-firing process is as follows: in, To save energy in coal gas produced by using an oxygen-enriched co-firing process. This represents the total number of slabs produced during the period when oxygen consumption is affected. The average interval between adjacent slab tapping times under air-assisted combustion process. The first under the oxygen-enriched co-firing process The moment the slab is removed from the furnace. For the oxygen-enriched co-firing process The moment the slab is removed from the furnace. for The average instantaneous flow rate of the heating furnace gas during the time period. This refers to the calorific value of the gas.

[0008] Furthermore, the specific calculation method for increasing slab production capacity using the oxygen-enriched co-firing process is as follows: in, To increase the output of slabs after adopting the oxygen-enriched co-firing process. The first period of time affected by oxygen use The weight of the slab after firing. This represents the total number of slabs that can be produced under an air-assisted combustion process with the same duration of oxygen influence. To achieve the same furnace entry temperature as slabs using the oxygen-enriched co-firing process, the first... The production output per slab based on a single slab.

[0009] Furthermore, the specific calculation method for the energy saving corresponding to the oxygen-enriched combustion process is as follows: in, To save energy by adopting the oxygen-enriched combustion process. The total oxygen consumption during the period affected by the oxygen-enriched combustion process. The conversion factor for fan power consumption is the equivalent air replacement volume per unit of oxygen.

[0010] Furthermore, the specific calculation method for the energy saving corresponding to the oxygen-enriched combustion process is as follows: in, To save energy through the use of oxygen-enriched combustion process. The exhaust gas temperature, The ambient air temperature, This is a conversion factor for the equivalent air replacement volume per unit of oxygen. It is the conversion coefficient for the amount of flue gas generated after a unit of air participates in the combustion reaction during fuel combustion. This represents the isobaric average specific heat capacity of the flue gas within the corresponding temperature range.

[0011] Furthermore, the cost of oxygen input... The specific calculation method is as follows: in, This refers to the unit price of oxygen. The total benefit after adopting the oxygen-enriched combustion process The specific calculation method is as follows: in, This refers to the unit price of gas. This is the unit price of the slab. This represents the unit price of electricity.

[0012] A system for evaluating the oxygen utilization efficiency of a slab heating furnace under an oxygen-enriched co-firing process includes: The coal gas energy saving calculation module calculates the coal gas energy saving corresponding to the oxygen-enriched combustion process during the oxygen consumption period of the oxygen-enriched combustion process, based on the difference between the time interval between adjacent slabs exiting the furnace under the oxygen-enriched combustion process and the time interval between adjacent slabs exiting the furnace under the air-assisted combustion process, combined with the heat power per unit time. The slab production increase calculation module calculates the slab production increase corresponding to the oxygen-enriched combustion process based on the difference between the production under the oxygen-enriched combustion process and the production under the air-assisted combustion process during the oxygen-influenced period of the oxygen-enriched combustion process. The power saving calculation module calculates the power saving energy corresponding to the oxygen-enriched combustion process during the oxygen consumption period of the oxygen-enriched combustion process, based on the corresponding fan power consumption after the oxygen quantity under the oxygen-enriched combustion process is equivalently replaced with the air quantity under the air-assisted combustion process. The heat saving calculation module calculates the heat loss of flue gas due to the reduction in total flue gas emissions during the oxygen consumption period of the oxygen-enriched combustion process, based on the air-assisted combustion process and the reduced amount of inert gas introduced into the air under the oxygen-enriched combustion process. The benefit evaluation module calculates the total benefit of adopting the oxygen-enriched co-firing process based on the sum of the energy saved in gas, the increased output of slabs, the energy saved in electricity, and the energy saved in heat. If the total benefit is greater than the oxygen input cost of the oxygen-enriched co-firing process, the benefit of oxygen-enriched co-firing is positive; if the total benefit is less than the oxygen input cost, the benefit of oxygen-enriched co-firing is negative; and if the total benefit is equal to the oxygen input cost, the benefit of oxygen-enriched co-firing is zero.

[0013] A computer program product includes a computer program / instructions that, when executed by a processor, implement the above-described method for evaluating the oxygen utilization efficiency of a slab heating furnace under an oxygen-enriched co-firing process.

[0014] The beneficial effects of this invention are as follows: 1. This invention establishes a standardized quantitative evaluation system for the benefits of oxygen-enriched co-firing, filling the technical gap of lacking a unified quantitative evaluation basis for the benefits of oxygen-enriched co-firing in slab heating furnaces in the metallurgical industry. It provides a unified standard for benefit accounting and decision-making for producers, production planners, and oxygen suppliers.

[0015] 2. By clearly defining the oxygen-influenced period of oxygen-enriched co-firing, the furnace residence lag of the heating effect of oxygen on slabs after its introduction is fully considered, avoiding the problem of distortion in output and energy consumption calculation data caused by the time and space misalignment between the oxygen introduction period and the benefit output period, thus ensuring the accuracy and reliability of the benefit assessment results.

[0016] 3. This invention calculates energy savings in four dimensions: gas energy saving, slab production increase, electricity energy saving, and heat energy saving. It covers both the explicit and implicit benefits brought by the oxygen-enriched co-firing process, and solves the problem of one-sided and large deviation in benefit evaluation caused by single-dimensional calculation. At the same time, each calculation formula is designed based on the operating parameters that can be measured and calibrated on-site in the heating furnace, without the need for complicated equipment performance deduction.

[0017] 4. This invention can directly determine the positive or negative benefits of oxygen-enriched co-firing by comparing the total revenue with the cost of oxygen input; at the same time, for non-positive benefit conditions, by calibrating the critical width of the slab, the applicable condition boundary of the oxygen-enriched co-firing process is clarified, which can guide the field to only use oxygen-enriched co-firing on slabs with a width greater than the critical width, and avoid ineffective oxygen input in narrow slab conditions, thus providing a quantitative basis for hot rolling production planning and scheduling. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the working area for the oxygen-enriched co-firing process.

[0019] Figure 2 This is a schematic diagram illustrating the effect of oxygen use on different time periods.

[0020] Figure 3 This is a block diagram of the oxygen utilization efficiency evaluation system for slab heating furnaces under the oxygen-enriched co-firing process of the present invention.

[0021] Explanation of reference numerals in the attached diagram: 1-Direction of billet movement inside the heating furnace; 2-Heating furnace; 3-Heating billet. Detailed Implementation

[0022] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0023] Example 1 A method for evaluating the oxygen utilization efficiency of a slab heating furnace under an oxygen-enriched co-firing process includes: During the oxygen-enriched co-firing process, based on the difference between the time interval between adjacent slabs exiting the furnace under the oxygen-enriched co-firing process and the time interval between adjacent slabs exiting the furnace under the air-assisted combustion process, and combined with the heat power per unit time, the gas energy saving corresponding to the oxygen-enriched co-firing process is obtained. During the period of oxygen consumption impact of the oxygen-enriched combustion process, the increase in slab output corresponding to the use of the oxygen-enriched combustion process is obtained based on the difference between the output under the oxygen-enriched combustion process and the output under the air-assisted combustion process. During the oxygen consumption period of the oxygen-enriched combustion process, the corresponding fan power consumption after the oxygen quantity under the oxygen-enriched combustion process is equivalently replaced with the air quantity under the air-assisted combustion process is used to obtain the energy saving corresponding to the oxygen-enriched combustion process. During the oxygen-enriched combustion process, based on the air-assisted combustion process, and taking the reduced amount of inert gas introduced into the air under the oxygen-enriched combustion process as a benchmark, the heat loss of flue gas due to the reduction in the total emission of flue gas is calculated, and the corresponding heat energy saving of the oxygen-enriched combustion process is obtained. The total benefit of using the oxygen-enriched co-firing process is obtained by summing the energy saved by the gas, the increased output of the slab, the energy saved by the electricity, and the energy saved by the heat. If the total benefit is greater than the oxygen input cost of the oxygen-enriched co-firing process, the oxygen-enriched co-firing benefit is positive; if the total benefit is less than the oxygen input cost, the oxygen-enriched co-firing benefit is negative; and if the total benefit is equal to the oxygen input cost, the oxygen-enriched co-firing benefit is zero.

[0024] If the oxygen-enriched co-firing benefit is negative or zero, then the critical width of the slab when the oxygen-enriched co-firing benefit is zero is determined. Slabs with a width greater than the critical width are subjected to the oxygen-enriched co-firing process, while slabs with a width less than or equal to the critical width are subjected to the air-assisted combustion process.

[0025] The production bottleneck of slab heating furnaces is strongly correlated with slab width. The wider the slab, the higher the heating load per unit length of slab, making the heating capacity of the furnace the core bottleneck of the rolling line capacity. In this case, oxygen-enriched co-firing can overcome the bottleneck by accelerating combustion speed and improving heating efficiency, and the production benefits can cover the oxygen input cost. Under narrow slab conditions, the heating capacity of the furnace is excessive, and the production bottleneck of the rolling line is not in the heating stage. The production increase and energy saving benefits of oxygen-enriched co-firing cannot cover the oxygen cost, resulting in negative benefits. By calibrating the critical width, the furnace is only used in the wide slab condition where positive benefits can be achieved with oxygen enrichment, while the narrow slab condition avoids ineffective oxygen input, maximizing the oxygen consumption benefits of single-furnace batch production. This provides a quantitative basis for production planning and scheduling. By optimizing the batch production of wide and narrow slabs, the supply and demand of the oxygen pipeline network can be matched, achieving coordinated optimization of production and oxygen supply.

[0026] As a specific implementation method, the oxygen usage influence period is specifically defined as: the oxygen administration time is... The oxygen supply was shut off at the following time. The time between the oxygen injection time and the time when the first billet from the oxygen-affected area is produced is The period during which oxygen use affects the system is... arrive .

[0027] like Figure 1 As shown, the continuous slab heating furnace is a walking beam or pusher-type continuous production equipment. The slab passes through the preheating section, heating section, and soaking section sequentially inside the furnace before exiting. Oxygen-enriched combustion is usually applied to the preheating section. Figure 2 As shown, after oxygen is introduced, it only heats the slabs entering the oxygen-enriched zone. These slabs have a fixed residence time in the furnace from the introduction of oxygen to their exit from the furnace. If the oxygen supply period is directly adjusted... As the period for benefit accounting, there may be a time and space misalignment where oxygen has been put into use but its effect is not reflected in the billets produced from the furnace, resulting in a mismatch between output and energy consumption data and oxygen use, and serious distortion of accounting results.

[0028] Furthermore, the specific calculation method for the energy saving of coal gas corresponding to the oxygen-enriched co-firing process is as follows: in, To save energy in coal gas after adopting an oxygen-enriched co-firing process. This represents the total number of slabs produced during the period when oxygen consumption is affected. The average interval between adjacent slab tapping times under air-assisted combustion process. The first under the oxygen-enriched co-firing process The moment when the slab billet is removed from the furnace. For the oxygen-enriched co-firing process The moment when the slab billet is removed from the furnace. for The average instantaneous flow rate of the heating furnace gas during the time period. This refers to the calorific value of the gas.

[0029] Oxygen-enriched co-firing increases the oxygen concentration of the combustion-supporting gas, accelerates the gas combustion reaction rate, and improves the flame temperature and furnace radiant heat exchange efficiency. This significantly shortens the heating time required for slabs to reach the target tapping temperature. In production, this translates to shorter tapping intervals between adjacent slabs and a faster production pace. Compared to the production pace of air-assisted combustion without oxygen enrichment, the reduced heating time due to the increased tapping pace of each slab corresponds to reduced empty burning of the furnace and consumption of heat-preserving gas. Multiplying this by the gas flow rate and calorific value for the corresponding time period allows for accurate calculation of the total heat savings from oxygen-enriched co-firing.

[0030] As a specific implementation method, the specific calculation method for increasing slab production corresponding to the oxygen-enriched co-firing process is as follows: in, To increase the output of slabs after adopting the oxygen-enriched firing process. The first period of time affected by oxygen use The weight of the slab after firing. This represents the total number of slabs that can be produced under an air-assisted combustion process with the same duration of oxygen influence. To achieve the same furnace entry temperature as slabs using the oxygen-enriched co-firing process, the first... The benchmark output per slab refers to the benchmark output within the corresponding statistical period, calculated based on the actual furnace temperature of the slab, the preset standard heating time and standard furnace exit rhythm under oxygen-free conditions.

[0031] The bottleneck in hot rolling lines is usually the heating capacity of the furnace, especially under wide slab conditions. Oxygen-enriched combustion improves the heating efficiency and heating capacity per unit time of the furnace, allowing more slabs to be heated and produced within the same production time, thus increasing total output. Output calculations must use the same production time as a unified benchmark, and combine this with the slab entry temperature to calculate standard output, eliminating the interference of furnace temperature differences on heating time and capacity calculations.

[0032] As a specific implementation method, the specific calculation method for the energy saving corresponding to the oxygen-enriched combustion process is as follows: in, To save energy by adopting the oxygen-enriched combustion process. The total oxygen consumption during the period affected by the oxygen-enriched combustion process. The conversion factor for fan power consumption is the equivalent air replacement volume per unit of oxygen.

[0033] , The power consumption of the fan per unit volume of air. It is the ratio of the average operating power of the fan to the average airflow delivered by the fan, calibrated through on-site measurement under actual operating conditions.

[0034] The power consumption of the combustion air blower in the heating furnace is positively correlated with the amount of combustion air delivered. Oxygen-enriched combustion uses pure oxygen instead of combustion air, directly reducing the air volume delivered by the combustion air blower and correspondingly lowering its operating power consumption. Pure oxygen is delivered under pressure through the oxygen pipeline network, eliminating the need for a combustion air blower. Therefore, the reduced power consumption due to the reduced air volume is the energy saving benefit of oxygen-enriched combustion. This can be achieved through conversion factors. It can directly convert oxygen consumption into the corresponding total energy saving of the fan, without the need for complicated fan performance curve calculations.

[0035] As a specific implementation method, the specific calculation method for the energy saving corresponding to the oxygen-enriched combustion process is as follows: in, To save energy through the use of oxygen-enriched combustion process. The exhaust gas temperature, Ambient air temperature, This is a conversion factor for the equivalent air replacement volume per unit of oxygen. It is the conversion coefficient for the amount of flue gas generated after a unit of air participates in the combustion reaction during fuel combustion. This represents the isobaric average specific heat capacity of the flue gas within the corresponding temperature range.

[0036] , The volume fraction of oxygen in the air is approximately 21%. .

[0037] The essence is the material balance ratio of the combustion reaction. Under certain fuel and combustion conditions, it is the ratio of the actual total volume of flue gas generated by the complete combustion of a unit volume of fuel to the total volume of air consumed by the complete combustion of a unit volume of fuel. It is calibrated by on-site measurement under actual working conditions.

[0038] Under conventional air-assisted combustion conditions, only about 21% of the oxygen in the combustion air participates in the gas combustion reaction, while the remaining approximately 79% of inert gases such as nitrogen do not participate in combustion. These gases are only heated to the flue gas temperature and then discharged with the flue gas. This portion of flue gas heat loss accounts for more than 50% of the total heat loss of the heating furnace, making it the most significant source of heat loss. Oxygen-enriched combustion uses pure oxygen to replace the combustion air, significantly reducing the amount of inert nitrogen introduced and directly lowering the total flue gas emissions. The less flue gas there is, the less heat is carried away from the furnace. The corresponding reduction in flue gas heat loss is the energy saving brought about by oxygen-enriched combustion, which essentially improves the thermal utilization efficiency of the heating furnace.

[0039] As one specific implementation method, the oxygen input cost The specific calculation method is as follows: in, This refers to the unit price of oxygen. The total benefit after adopting the oxygen-enriched combustion process The specific calculation method is as follows: in, This refers to the unit price of gas. This is the unit price of the slab. This represents the unit price of electricity.

[0040] To better illustrate the technical solution of this invention, on-site test data are used for comparison, as follows: For ordinary carbon steel Q235B, the specifications of a single slab are: thickness 230mm × width 2300mm × length 10500mm; the weight of a single slab is 28 tons. The question asks for the furnace weight of the nth slab during the oxygen-affected period. The reference weight under the air-assisted combustion process Both are 28 tons; the slab entry temperature is 25℃; the target exit temperature is 1200℃.

[0041] The duration from the preset oxygen injection time to the time when the first billet from the oxygen-affected area is expelled from the furnace. The oxygen administration time is 15 minutes. The value is 0, and the oxygen supply is stopped at [time]. The total duration of the oxygen-affected period is 45 minutes, with a time limit of 60 minutes. In the following calculations, data for both air-assisted combustion and oxygen-enriched combustion processes are obtained within this timeframe.

[0042] Under air-assisted combustion process, the average interval between adjacent slab tapping times With a processing time of 2 minutes per piece, the theoretical total number of slabs that can be produced within 45 minutes is... There are 22 pieces. =616 tons, the average instantaneous flow rate of the heating furnace gas under the air-assisted combustion process is 12000 m³ / s. 3 / h, the average airflow rate delivered by the fan is 85000 m³ / h. 3 The average operating power of the blower is 170kW per hour, and the total power consumption in 45 minutes is 127.5kWh. Under this operating condition, there is no oxygen input cost; the core benefit is the basic profit corresponding to slab production, without the additional energy-saving or production-increasing benefits of oxygen enrichment.

[0043] Under the oxygen-enriched co-firing process, oxygen is supplied under pressure from the plant's oxygen pipeline network, eliminating the need for blower operation. The actual furnace exit interval between adjacent slabs remains stable at 100 seconds per slab, and the total number of slabs produced during the 45-minute oxygen consumption period is affected. There are 27 blocks, and the cumulative oxygen consumption is... 12000m 3 Average instantaneous flow rate of gas in heating furnace under oxygen-enriched co-firing process 11500m 3 / h.

[0044] Energy saving of coal gas after adopting oxygen-enriched co-firing process . h, h, h, kJ.

[0045] Increased slab production using oxygen-enriched co-firing process . ton.

[0046] Energy saving after adopting oxygen-enriched combustion process The power consumption of the fan per unit volume of air was determined through on-site measurement and calibration. 0.002 kWh / m 3 , kWh / m 3 , kWh.

[0047] Energy saving through oxygen-enriched combustion process Calibration was performed through on-site testing under actual working conditions. The isobaric average specific heat capacity of flue gas within the corresponding temperature range It is 1.38 kJ / (m 3 ·℃), flue gas temperature The ambient air temperature is 180℃. It is 25℃. kJ.

[0048] Oxygen input cost The unit price of oxygen It is 0.8 yuan / m 3 , Yuan.

[0049] Total benefits after oxygen-enriched co-firing process The unit price of gas for Yuan / kJ, slab unit price The price is 3800 yuan per unit, which is the unit price of electricity. It is 0.65 yuan / kWh. 532,448.695 yuan.

[0050] Net benefits from oxygen-enriched co-firing The total revenue was 522,848.695 yuan, far exceeding the cost of oxygen input, indicating a positive benefit from oxygen-enriched co-firing.

[0051] Example 2 refer to Figure 3 A system for evaluating the oxygen utilization efficiency of a slab heating furnace under an oxygen-enriched co-firing process, comprising: The coal gas energy saving calculation module calculates the coal gas energy saving corresponding to the oxygen-enriched combustion process during the oxygen consumption period of the oxygen-enriched combustion process, based on the difference between the time interval between adjacent slabs exiting the furnace under the oxygen-enriched combustion process and the time interval between adjacent slabs exiting the furnace under the air-assisted combustion process, combined with the heat power per unit time. The slab production increase calculation module calculates the slab production increase corresponding to the oxygen-enriched combustion process based on the difference between the production under the oxygen-enriched combustion process and the production under the air-assisted combustion process during the oxygen-influenced period of the oxygen-enriched combustion process. The power saving calculation module calculates the power saving energy corresponding to the oxygen-enriched combustion process during the oxygen consumption period of the oxygen-enriched combustion process, based on the corresponding fan power consumption after the oxygen quantity under the oxygen-enriched combustion process is equivalently replaced with the air quantity under the air-assisted combustion process. The heat saving calculation module calculates the heat loss of flue gas due to the reduction in total flue gas emissions during the oxygen consumption period of the oxygen-enriched combustion process, based on the air-assisted combustion process and the reduced amount of inert gas introduced into the air under the oxygen-enriched combustion process. The benefit evaluation module calculates the total benefit of adopting the oxygen-enriched co-firing process based on the sum of the energy saved in gas, the increased output of slabs, the energy saved in electricity, and the energy saved in heat. If the total benefit is greater than the oxygen input cost of the oxygen-enriched co-firing process, the benefit of oxygen-enriched co-firing is positive; if the total benefit is less than the oxygen input cost, the benefit of oxygen-enriched co-firing is negative; and if the total benefit is equal to the oxygen input cost, the benefit of oxygen-enriched co-firing is zero.

[0052] Example 3 A computer program product includes a computer program / instructions that, when executed by a processor, implement the oxygen utilization efficiency evaluation method for slab heating furnaces under the oxygen-enriched co-firing process in Embodiment 1.

[0053] The contents not described in detail in this specification are prior art known to those skilled in the art. Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0054] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0055] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0056] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit its scope of protection. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that after reading the present invention, they can still make various changes, modifications or equivalent substitutions to the specific implementation of the invention, but these changes, modifications or equivalent substitutions are all within the scope of protection of the pending claims of the invention.

Claims

1. A method for evaluating the oxygen utilization efficiency of a slab heating furnace under an oxygen-enriched co-firing process, characterized in that, include: During the oxygen-enriched co-firing process, based on the difference between the time interval between adjacent slabs exiting the furnace under the oxygen-enriched co-firing process and the time interval between adjacent slabs exiting the furnace under the air-assisted combustion process, and combined with the heat power per unit time, the gas energy saving corresponding to the oxygen-enriched co-firing process is obtained. During the period of oxygen consumption impact of the oxygen-enriched combustion process, the increase in slab output corresponding to the use of the oxygen-enriched combustion process is obtained based on the difference between the output under the oxygen-enriched combustion process and the output under the air-assisted combustion process. During the oxygen consumption period of the oxygen-enriched combustion process, the corresponding fan power consumption after the oxygen quantity under the oxygen-enriched combustion process is equivalently replaced with the air quantity under the air-assisted combustion process is used to obtain the energy saving corresponding to the oxygen-enriched combustion process. During the oxygen-enriched combustion process, based on the air-assisted combustion process, and taking the reduced amount of inert gas introduced into the air under the oxygen-enriched combustion process as a benchmark, the heat loss of flue gas due to the reduction in the total emission of flue gas is calculated, and the corresponding heat energy saving of the oxygen-enriched combustion process is obtained. The total benefit of using the oxygen-enriched co-firing process is obtained by summing the energy saved by the gas, the increased output of the slab, the energy saved by the electricity, and the energy saved by the heat. If the total benefit is greater than the oxygen input cost of the oxygen-enriched co-firing process, the oxygen-enriched co-firing benefit is positive; if the total benefit is less than the oxygen input cost, the oxygen-enriched co-firing benefit is negative; and if the total benefit is equal to the oxygen input cost, the oxygen-enriched co-firing benefit is zero.

2. The oxygen utilization efficiency evaluation system for slab heating furnaces according to claim 1, characterized in that, Also includes: If the oxygen-enriched co-firing benefit is negative or zero, then the critical width of the slab when the oxygen-enriched co-firing benefit is zero is determined. Slabs with a width greater than the critical width are subjected to the oxygen-enriched co-firing process, while slabs with a width less than or equal to the critical width are subjected to the air-assisted combustion process.

3. The oxygen utilization efficiency evaluation system for slab heating furnaces according to claim 1, characterized in that, The specific time period affected by oxygen consumption is as follows: The oxygen supply time is set as follows The oxygen supply was shut off at the following time. The time between the oxygen injection time and the time when the first billet from the oxygen-affected area is produced is The period during which oxygen use affects the system is... arrive .

4. The oxygen utilization efficiency evaluation system for slab heating furnaces according to claim 1, characterized in that, The specific calculation method for the energy saving of coal gas corresponding to the oxygen-enriched co-firing process is as follows: in, To save energy in coal gas after adopting an oxygen-enriched co-firing process. This represents the total number of slabs produced during the period when oxygen consumption is affected. The average interval between adjacent slab tapping times under air-assisted combustion process. For the first oxygen-enriched co-firing process The moment when the slab billet is removed from the furnace. For the oxygen-enriched co-firing process The moment when the slab billet is removed from the furnace. for The average instantaneous flow rate of the heating furnace gas during the time period. This refers to the calorific value of the gas.

5. The oxygen utilization efficiency evaluation system for slab heating furnaces according to claim 4, characterized in that, The specific calculation method for increasing slab production using the oxygen-enriched co-firing process is as follows: in, To increase the output of slabs after adopting the oxygen-enriched firing process. The first period of time affected by oxygen use The weight of the slab after firing. This represents the total number of slabs that can be produced under an air-assisted combustion process with the same duration of oxygen influence. To achieve the same furnace entry temperature as slabs using the oxygen-enriched co-firing process, the first... The production output per slab based on a single slab.

6. The oxygen utilization efficiency evaluation system for slab heating furnaces according to claim 5, characterized in that, The specific calculation method for the energy saving corresponding to the oxygen-enriched combustion process is as follows: in, To save energy by adopting the oxygen-enriched combustion process. The total oxygen consumption during the period affected by the oxygen use in the oxygen-enriched combustion process. The conversion factor for fan power consumption is the equivalent air replacement volume per unit of oxygen.

7. The oxygen utilization efficiency evaluation system for slab heating furnaces according to claim 6, characterized in that, The specific calculation method for the energy saving corresponding to the oxygen-enriched combustion process is as follows: in, To save energy through the use of oxygen-enriched combustion process. The exhaust gas temperature, Ambient air temperature, This is a conversion factor for the equivalent air replacement volume per unit of oxygen. It is the conversion coefficient for the amount of flue gas generated after a unit of air participates in the combustion reaction during fuel combustion. This represents the isobaric average specific heat capacity of the flue gas within the corresponding temperature range.

8. The oxygen utilization efficiency evaluation system for slab heating furnaces according to claim 7, characterized in that: The cost of oxygen input The specific calculation method is as follows: in, This refers to the unit price of oxygen. The total benefit after adopting the oxygen-enriched combustion process The specific calculation method is as follows: in, This refers to the unit price of gas. This is the unit price of the slab. This represents the unit price of electricity.

9. A system for evaluating the oxygen utilization efficiency of a slab heating furnace under an oxygen-enriched co-firing process, characterized in that, include: The coal gas energy saving calculation module calculates the coal gas energy saving corresponding to the oxygen-enriched combustion process during the oxygen consumption period of the oxygen-enriched combustion process, based on the difference between the time interval between adjacent slabs exiting the furnace under the oxygen-enriched combustion process and the time interval between adjacent slabs exiting the furnace under the air-assisted combustion process, combined with the heat power per unit time. The slab production increase calculation module calculates the slab production increase corresponding to the oxygen-enriched combustion process based on the difference between the production under the oxygen-enriched combustion process and the production under the air-assisted combustion process during the oxygen-influenced period of the oxygen-enriched combustion process. The power saving calculation module calculates the power saving energy corresponding to the oxygen-enriched combustion process during the oxygen consumption period of the oxygen-enriched combustion process, based on the corresponding fan power consumption after the oxygen quantity under the oxygen-enriched combustion process is equivalently replaced with the air quantity under the air-assisted combustion process. The heat saving calculation module calculates the heat loss of flue gas due to the reduction in total flue gas emissions during the oxygen consumption period of the oxygen-enriched combustion process, based on the air-assisted combustion process and the reduced amount of inert gas introduced into the air under the oxygen-enriched combustion process. The benefit evaluation module calculates the total benefit of adopting the oxygen-enriched co-firing process based on the sum of the energy saved in gas, the increased output of slabs, the energy saved in electricity, and the energy saved in heat. If the total benefit is greater than the oxygen input cost of the oxygen-enriched co-firing process, the benefit of oxygen-enriched co-firing is positive; if the total benefit is less than the oxygen input cost, the benefit of oxygen-enriched co-firing is negative; and if the total benefit is equal to the oxygen input cost, the benefit of oxygen-enriched co-firing is zero.

10. A computer program product comprising a computer program / instructions, characterized in that, When the computer program / instruction is executed by the processor, it implements the oxygen utilization efficiency evaluation method for slab heating furnace under the oxygen-enriched co-firing process as described in any one of claims 1 to 8.

Images