CN115330039A - A method for measuring carbon emissions in all processes of iron and steel smelting - Google Patents

Abstract

A method for measuring carbon emissions in all processes of iron and steel smelting, characterized in that the method comprises the following steps: Step 1: Collect electricity consumption data, steel output and pig iron output at the gate of iron and steel smelting enterprises, and based on historical data Obtain the association relationship between the above-mentioned data; Step 2, estimate the current steel output and the current pig iron output based on the association relationship and the real-time gate electricity consumption; Step 3, obtain all the processes of the iron and steel smelting enterprise in the steel smelting process, The carbon emission intensity of each process is calculated to obtain the real-time total carbon emission of the iron and steel smelting enterprise. The calculation process of the invention is simple, the calculation amount is very small, the calculation result is accurate, and the real-time degree is high.

Description

A carbon emission measurement method in all processes of iron and steel smelting

technical field

The invention relates to the field of iron and steel smelting, and more specifically, relates to a method for measuring carbon emissions in all processes of iron and steel smelting.

Background technique

The "double carbon" goal refers to the goal of reducing the emission of carbon dioxide as much as possible in the process of industrial production, so that the emission of carbon dioxide and the absorption of carbon dioxide in people's production and life can be as balanced as possible. In order to achieve the "double carbon" goal, a large number of key carbon emission enterprises have begun to realize the accounting and monitoring of carbon emissions, and through the establishment of a full-process, fine-grained carbon emission analysis system, to achieve accurate estimation and control of carbon emissions.

However, since the carbon emission accounting in the iron and steel industry is still in the initial stage of research, there are various problems in the actual accounting process. For example, the accounting standards and accounting methods in the industry have not yet been unified. Many iron and steel smelting links have made it too difficult to monitor actual carbon emissions. The high price of the real-time carbon emissions monitoring system CEMS (Continuous Emissions Monitoring Systems) has also made the system difficult to popularize. Problems that are difficult to cover throughout the process.

On the other hand, most iron and steel enterprises consume a large amount of electric energy during the iron and steel smelting process, and when the iron and steel smelting steps and procedures are determined, there is a certain relationship between the consumption of electric energy and the actual steel production. However, in the prior art, there is no accurate method for obtaining the carbon emission in the iron and steel smelting process based on the consumption of electric energy.

In view of the above problems, the present invention provides a new method for measuring carbon emissions in all iron and steel smelting processes.

Contents of the invention

In order to solve the deficiencies in the prior art, the object of the present invention is to provide a carbon emission measurement method in all iron and steel smelting processes. This method collects the electricity consumption data at the gate of iron and steel smelting enterprises, and obtains the relationship between the electricity consumption and the actual steel production and pig iron production, so as to estimate the iron and steel smelting process through the internal correlation between steel production and carbon emissions Real-time total carbon emissions in .

The present invention adopts the following technical solutions. A carbon emission reduction method in all processes of iron and steel smelting, the method includes the following steps: Step 1, collect the data of electricity consumption at the gate of the iron and steel smelting enterprise, steel production and pig iron production, and obtain the relationship between the above data based on historical data relationship; Step 2, estimate the current steel production and current pig iron production based on the relationship and real-time power consumption at the gate; Step 3, obtain all the processes in the iron and steel smelting process of the iron and steel smelting enterprise, and calculate the carbon emission intensity of each process Calculation, so as to obtain the real-time total carbon emissions of iron and steel smelting enterprises.

Preferably, the correlation includes a first regression equation and a second regression equation; wherein, the first regression equation is used to characterize the correlation between historical steel production and historical pig iron production; the second regression equation is used to characterize historical gate power consumption The relationship between data and historical steel production and historical pig iron production.

Preferably, the first regression equation X _steel is a polynomial regression equation

In the formula, X _steel (t) is the historical steel output at time t,

X _iron (t) is the historical pig iron production at time t,

α ₁ , α ₂ , . . . , α _n and C ₁ are coefficients of polynomials, respectively.

Preferably, the second regression equation is a linear regression equation

E _elc (t)＝C ₂ +β ₁ X _iron (t)+β ₂ X _steel (t)

In the formula, E _elc (t) is the historical gate power consumption data at time t,

β ₁ , β ₂ and C ₂ are coefficients of the linear equation, respectively.

Preferably, all processes include coking process, sintering process, blast furnace ironmaking process, converter steelmaking process and continuous casting and hot rolling process; the real-time total carbon emission of iron and steel smelting enterprises is equal to the real-time carbon emission of each process in all processes and.

Preferably, the carbon emission in the i-th process is

E _process-i = B _process-i +P _process-i

Among them, B _process-i is the carbon emission generated by the combustion of raw materials input into the i-th process;

P _process-i is the carbon emissions generated by the raw materials input into the i-th process due to other processes other than combustion.

Preferably, the formula for calculating the carbon emissions of raw materials input into the i-th process due to combustion is:

Among them, j is the raw material number in the i-th process, and the value ranges from 1 to J,

Q _fuel,j is the combustion consumption of the j-th raw material in the i-th process,

EFG _fuel,j is the carbon content in the j-th raw material in the i-th process.

Preferably, the formula for calculating the carbon emissions of raw materials input into the i-th process due to other processes other than combustion is

Among them, Q _in-mat,j is the input amount of the jth raw material in the i-th process,

Q _out-mat,j is the output of the jth raw material in the i-th process,

EFP _mat,j is the emission factor of non-combustion other processes of the jth raw material in the i process.

Preferably, the output quantity Q _out-mat,j of the jth raw material in the i-th process includes the output quantity of the jth raw material and the output quantity of the combustion product of the jth raw material.

Preferably, the input amount Q _in-mat,j of the jth raw material in the i-th process, and the combustion consumption Q _fuel,j of the j-th raw material in the i-th process are based on the current steel output and the current pig iron output Obtained by reverse derivation.

The beneficial effect of the present invention is that, compared with the prior art, the present invention provides a method for measuring carbon emissions in all iron and steel smelting processes. This method collects the electricity consumption data at the gate of iron and steel smelting enterprises, and obtains the relationship between the electricity consumption and the actual steel production and pig iron production, so as to estimate the iron and steel smelting process through the internal correlation between steel production and carbon emissions Real-time total carbon emissions in . The calculation process of the invention is simple, the calculation amount is very small, the calculation result is accurate, and the real-time performance is high.

The beneficial effects of the present invention also include:

1. The present invention eliminates the problem that it is difficult to obtain real-time monitoring due to the long calculation time scale generated in the raw material analysis process. Since the real-time carbon emission in the present invention can be obtained according to the real-time gate electricity data of the iron and steel smelting enterprise, the actual consumption of various raw materials at the current moment can be ignored, so as to obtain the accurate carbon emission.

2. In the prior art, carbon emission analysis for raw material usage is often used. This method cannot accurately calculate the carbon emission in each process. This makes it possible to estimate the total carbon emission of the enterprise, but It is difficult to know which process has too high carbon emission and which process can be easily reduced through improvement. However, the method of the present invention accurately obtains the amount of carbon emissions under each process by reversely deriving the amount of raw materials, so as to effectively guide the reduction of carbon emissions under each process.

3. The method of the present invention no longer requires iron and steel enterprises to popularize the CEMS system, which greatly reduces the accounting cost, and can obtain large-scale, accurate, and real-time carbon emission measurement without adding any new devices or equipment, which is conducive to popularization and coverage.

Description of drawings

Fig. 1 is a schematic diagram of steps of a method for measuring carbon emissions in all iron and steel smelting processes of the present invention;

Fig. 2 is a schematic diagram of the relationship between the historical gate power consumption data, historical steel production, and historical pig iron production in a carbon emission measurement method in all iron and steel smelting processes of the present invention;

Fig. 3 is a schematic diagram of the real-time steel production and real-time pig iron production obtained based on the correlation in the carbon emission measurement method in all iron and steel smelting processes of the present invention;

Fig. 4 is a schematic diagram of the confidence degree of the first regression equation in the carbon emission measurement method in all processes of iron and steel smelting in the present invention;

Fig. 5 is a schematic diagram of the confidence degree of the second regression equation in the carbon emission measurement method in all processes of iron and steel smelting in the present invention;

Fig. 6 is a schematic diagram of carbon emission measurement in each process in an embodiment of a carbon emission measurement method in all iron and steel smelting processes of the present invention;

Fig. 7 is a schematic diagram of the carbon emission ratio of each process in an embodiment of a method for measuring carbon emissions in all processes of iron and steel smelting according to the present invention;

Fig. 8 is a schematic diagram of real-time carbon emissions changing with time in an embodiment of a method for measuring carbon emissions in all iron and steel smelting processes of the present invention.

Detailed ways

The application will be further described below in conjunction with the accompanying drawings. The following examples are only used to illustrate the technical solutions of the present invention more clearly, but not to limit the protection scope of the present application.

Fig. 1 is a schematic diagram of steps of a method for measuring carbon emissions in all processes of iron and steel smelting according to the present invention. As shown in FIG. 1 , the present invention relates to a carbon emission reduction method in all processes of iron and steel smelting, and the method includes steps 1 to 3.

Step 1. Collect the electricity consumption data, steel output and pig iron output of iron and steel smelting enterprises, and obtain the correlation between the above data based on historical data.

It can be understood that the present invention can collect the electricity consumption data at the gate of the iron and steel smelting enterprise, and estimate the real-time steel output and pig iron output of the iron and steel smelting enterprise according to the electricity consumption data. Among them, the electricity consumption at the gate can be the sum of the electricity used by the main iron and steel smelting equipment of the iron and steel smelting enterprise.

Of course, the power consumption at the gateway here can also be just the power consumption of the most initial or most representative piece of equipment among all iron and steel smelting equipment. At this time, the power consumption of other large equipment can be inferred based on the representative power consumption of this one. For example, when the coking program uses 10Kw.h of electricity, the continuous casting and hot rolling equipment can correspondingly need to use 100Kw.h of electricity to ensure full utilization of the coked raw materials. Therefore, if the power consumption at the gate is 1Kw.h, the individual power consumption of each equipment in all steps of the iron and steel smelting enterprise can be reasonably evaluated.

Specifically, the present invention can express the relationship between data by establishing a regression equation. The data used to establish the regression equation here should be objective and accurate historical data. Among them, the electricity consumption data at the gateway can be obtained from the data collected by the electric meter, and the steel output and pig iron output can also be obtained based on the actual accounting data of the iron and steel smelting enterprises.

Fig. 2 is a schematic diagram of the relationship between historical power consumption data at gates, historical steel production, and historical pig iron production in a carbon emission measurement method in all iron and steel smelting processes of the present invention. As shown in FIG. 2 , in one embodiment of the present invention, the historical gate power consumption data, historical steel production, and historical pig iron production in each month can be obtained in units of months. Of course, the present invention can also compile historical data with any different time scales, for example, in units of days and hours, and the source of these data is obtained based on the actual output of iron and steel enterprises.

After obtaining the above data, the corresponding regression equation can be established. Specifically, in the present invention, the correlation between steel output and electricity consumption at the gate can be established by using a multidimensional polynomial regression equation.

Preferably, the first regression equation X _steel is a polynomial regression equation

In the formula, X _steel (t) is the historical steel output at time t,

X _iron (t) is the historical pig iron production at time t,

α ₁ , α ₂ , . . . , α _n and C ₁ are coefficients of polynomials, respectively.

According to the selection method of the above regression equation, it can be known how the actual electricity consumption at the gate affects the actual output of steel products. After the correlation of the above data is confirmed, the second regression equation can be further obtained. In an embodiment of the present invention, when the value of the highest order item in the regression equation is selected to be 2, the best fitting effect of the regression equation is obtained.

Preferably, the second regression equation is a linear regression equation

E _elc (t)＝C ₂ +β ₁ x _iron (t)+β ₂ X _steel (t)

In the formula, E _elc (t) is the historical gate power consumption data at time t,

β ₁ , β ₂ and C ₂ are coefficients of the linear equation, respectively.

On the basis of the first regression equation, the relationship between the power consumption data at the gateway and the output of steel and pig iron is established. For the convenience of calculation, the equation here is a linear equation, which greatly reduces the amount of calculation.

The values of various coefficients can be obtained by fitting and solving historical data.

Step 2: Estimating the current steel production and current pig iron production based on the association relationship and real-time power consumption at the gateway.

Fig. 3 is a schematic diagram of real-time steel production and real-time pig iron production obtained based on correlation in a carbon emission measurement method in all processes of iron and steel smelting according to the present invention. As shown in Figure 3, after the first regression equation and the second regression equation are determined, the real-time power consumption data at the gateway can be substituted into the equation, and the current steel production and pig iron production can be estimated. In Fig. 3, the difference between the estimated amount calculated by the invented method and the actual used amount is small.

In the present invention, a plurality of historical data can also be used to obtain the confidence levels of the first and second regression equations.

Fig. 4 is a schematic diagram of the confidence degree of the first regression equation in the carbon emission measurement method in all iron and steel smelting processes of the present invention. Fig. 5 is a schematic diagram of the confidence degree of the second regression equation in the carbon emission measurement method in all iron and steel smelting processes of the present invention. As shown in Fig. 4 and Fig. 5, in the present invention, relevant data at a certain historical moment or at a certain current moment can be collected, respectively substituted into the first regression equation and the second regression equation after the coefficients are determined, and can obtain Computational deviation at a certain moment. The corresponding data at the moment of the puppet here is the case described in Figure 4 and Figure 5. In addition, the residuals in Figure 4 and Figure 5 can be the estimated value obtained by considering the equation and the actual value collected actually. the difference between. The specific calculation method of this residual can be realized by considering any residual calculation method in the prior art.

Step 3: Obtain all the processes of iron and steel smelting enterprises in the process of smelting iron and steel, and calculate the carbon emission intensity of each process, so as to obtain the real-time total carbon emissions of iron and steel smelting enterprises.

After obtaining the estimated current steel production and current pig iron production, the present invention can calculate the carbon emissions in each actual process of iron and steel smelting according to the above data, and then sum them to obtain the total carbon emissions Measured.

In the present invention, the long process steelmaking is taken as an example, and the process is divided into multiple steps. Preferably, all processes include coking process, sintering process, blast furnace ironmaking process, converter steelmaking process and continuous casting and hot rolling process; the real-time total carbon emission of iron and steel smelting enterprises is equal to the real-time carbon emission of each process in all processes and.

In the actual application process, basically every steelmaking process contains a certain degree of carbon emissions. These carbon emissions can be the carbon emissions generated by the actual combustion of raw materials in this process, or they can be caused by other processes other than combustion. carbon emissions. Since the present invention uses the data of the electric energy meter at the gate to estimate the output of steel, the error of this calculation method is relatively minimal.

Preferably, the carbon emission in the i-th process is

E _process-i = B _process-i +P _process-i

Among them, B _process-i is the carbon emission generated by the combustion of raw materials input into the i-th process;

P _process-i is the carbon emissions generated by the raw materials input into the i-th process due to other processes other than combustion.

According to the principles described above, the present invention can generally measure carbon emissions from two aspects, one is the carbon emissions generated by combustion, and the other is the carbon emissions generated by other methods.

Preferably, the formula for calculating the carbon emissions of raw materials input into the i-th process due to combustion is:

Among them, j is the raw material number in the i-th process, and the value ranges from 1 to J,

Q _fuel,j is the combustion consumption of the j-th raw material in the i-th process,

EFC _fuel,j is the carbon content in the j-th raw material in the i-th process.

It can be understood that a large amount of carbon emissions in the present invention should come from the carbon emissions produced by burning raw materials. The actual burning amount of raw materials can be deduced backwards based on the estimation results in step 2. This calculation process can be accurately obtained according to the actual experience of iron and steel smelting enterprises. In addition, for a certain raw material, the carbon emission in the combustion process is actually determined according to the carbon content of the raw material. The carbon content can be obtained indirectly according to the purity and chemical formula of the raw material.

The carbon content in the raw materials in the present invention can be obtained by referring to the relevant regulations in the "Guidelines for Calculating and Reporting Greenhouse Gas Emissions of Iron and Steel Manufacturing Enterprises in China", and can also achieve specific accounting according to the corresponding accounting methods in the guidelines.

For example, according to the purity and chemical formula of quartz stone, dolomite, coke oven gas and other raw materials, the carbon content in the raw materials can be obtained. Assuming that the raw materials have been completely burned in the current process, the raw materials can be obtained according to the carbon content. Carbon emissions in the case of a combustion consumption.

Preferably, the formula for calculating the carbon emissions of raw materials input into the i-th process due to other processes other than combustion is

Among them, Q _in-mat,j is the input amount of the jth raw material in the i-th process,

Q _out-mat,j is the output of the jth raw material in the i-th process,

EFP _mat,j is the emission factor of non-combustion other processes of the jth raw material in the i process.

On the other hand, it is considered that in the main combustion process, the raw materials input into the current process may not be sufficiently burned. At this time, the actual combustion amount is not completely equal to the actual raw material input amount. The proportional relationship between the combustion amount and the input amount can be obtained according to the methods in the prior art. Generally speaking, there is a certain degree of deviation in the utilization efficiency of raw materials according to the equipment used in the process.

In the present invention, after the estimation in step 2, what can be actually calculated should be the value of combustion consumption Q _fuel,j , and according to the empirical data of the equipment used in the process, the input quantity Q of raw materials can be deduced inversely _in-mat,j . According to the corresponding content in the next step, the input quantity of the raw material in the next step can also be obtained, that is, the output quantity Q _out-mat,j of the raw material in this step. By taking the difference between the two, the actual amount of raw materials consumed by other processes besides combustion can be obtained in this process.

By estimating the carbon emission factor of this process, the carbon emissions of other non-combustion processes can be solved. The emission factor here can also be calculated taking into account the essential properties of the process. For example, in the coking process, in addition to the carbon emissions produced by combustion, which may be caused by steam smoldering the cleaned coal, the emission factors of each raw material in this step can be obtained based on empirical data and other methods.

Preferably, the output quantity Q _out-mat,j of the jth raw material in the i-th process includes the output quantity of the jth raw material and the output quantity of the combustion product of the jth raw material.

It should be noted that in the present invention, the output quantity of the jth raw material is not only obtained according to the input quantity of the next process, but also can be calculated according to the by-products produced in the current process. These by-products may not be fully utilized in the next process, but by monitoring the current process, the amount of these by-products can be fully obtained, and the amount of these by-products can be converted into the amount of raw materials before consumption. Through this Only in this way can the actual consumption of other processes of non-burning raw materials be obtained.

Preferably, the input amount Q _in-mat,j of the jth raw material in the i-th process, and the combustion consumption Q _fuel,j of the j-th raw material in the i-th process are based on the current steel output and the current pig iron output Obtained by reverse derivation.

It can be understood that, as mentioned above, in the present invention, the input, output and actual consumption of raw materials are deduced based on the estimated values in step 2 of the current steel production and the current pig iron production. Therefore, the present invention can obtain real-time calculation of carbon emissions without actually measuring how raw materials are consumed, and at the same time, does not require a relatively large time scale.

Fig. 6 is a schematic diagram of carbon emission measurement in each process in an embodiment of a carbon emission measurement method in all iron and steel smelting processes of the present invention. As shown in Figure 6, in one embodiment of the present invention, it can be assumed that the coking process and the sintering process are carried out in parallel, and the coke realized by coking and the ore realized by sintering are synchronously input into the blast furnace ironmaking step, after blast furnace ironmaking , the raw material is converted into molten iron and continues to be refined. The steel raw materials are obtained after the subsidy enters the converter steelmaking, and finally the steel output is realized after continuous casting and hot rolling.

In the embodiment of the present invention, the carbon emissions of each of the above steps are estimated.

First of all, in the coking process, the input carbon-containing substances are mainly washed coal, which can be steamed in the coke oven to obtain the coke required for blast furnace ironmaking. The carbon-containing substances output by this process mainly include Coke, crude benzene, coal tar, the exhaust gas is coke oven gas, and there is a certain amount of release of coke oven gas.

It can be seen from the content shown in Fig. 6 that in the coking process, the raw materials to be used include steam, oxygen, and cleaned coal. In addition, the blast furnace gas from the blast furnace ironmaking link and the coke oven gas generated after coking can also be mixed and fed back to the input end of the coking link as raw materials for the coking process. In Figure 6, for every 512.6kg of clean coal consumed, about 384 cubic meters of blast furnace gas and 21 cubic meters of coke oven gas are required at the same time. After this process, about 367.5kg of coke, 3.6kg of crude benzene, 16.1kg of coke oil and 165 cubic meters of coke oven gas can be produced.

At this point, the carbon emissions under this step can be

_EcF = _BCF + _PCF

Among them, B _CF and PC _CF are the combustion carbon emissions and non-combustion carbon emissions in the coking process, respectively.

Specifically, B _CF ＝Q _coal EF _coal -Q _coke EF _coke -Q _ben EF _ben -Q _tar EF _tar +G _CF,dis EFC _BFG , where Q _coal is the amount of washed coal as the main input raw material, EF _coal is the carbon content of the corresponding raw material. In addition, part of the carbon generated from raw clean coal will be absorbed by coke, crude benzene, and coke oil during the furnace production process. Therefore, it is necessary to subtract this part of the re-absorbed carbon content. Therefore, Q _coke , Q _ben and Q _tar are the amounts of the above-mentioned substances, respectively, and EF _coke , EF _ben and EF _tar are respectively the carbon contents of the above-mentioned substances. In addition, EFC _BFG is the carbon content of the coke oven gas, and G _CF,dis is the released coke oven gas.

Because the content Q _coal of all substances in the present invention, Q _coke , Q _ben and Q _tar etc. are all derived by adopting the method in step 2, therefore do not include the consumption in other technological process, this content and real The content is different, and it can only represent the amount actually involved in the coking reaction. Therefore, after this formula, it is necessary to supplement the carbon emissions caused by the released coke oven gas.

On the other hand, in the coking process, in addition to the carbon emissions caused by combustion, there are also carbon emissions caused by other processes. Specifically, P _CF =G _CF,dis EFP _BFG +G _CF,re EFP _BFG . Among them, EFP _BFG is the emission factor of other non-combustion processes, and G _CF,re is the amount of coke oven gas recovered again.

It should be noted that among the products produced, part of the coke oven gas will be released, and during the process of release, part of the coke oven gas will be discharged into the air through combustion to produce harmless carbon dioxide, and the other part cannot be completely released due to technological factors. Combustion, so emissions can be determined from non-combustion emission factors. The recovered coke oven gas can be reused by the coking process of the present invention and generate part of carbon emissions.

It should be noted that the parameter G _CF,re here can be inversely obtained according to the output of steel and pig iron calculated in step 2. However, the content of the released coke oven gas cannot be accurately obtained by reverse deduction by the method of the present invention. However, in the present invention, it can be assumed that the amount of released coke oven gas accounts for the proportion of recovered coke oven gas, so assuming that this part of released coke oven gas has not only passed through non-combustion release of carbon, but also through the process of burning and releasing carbon, so G _CF,dis (EFC _BFG +EEP _BFG ) is used to express its carbon release. Thus, the calculation of the carbon release amount of the coking process in the present invention is completed.

Using a similar method, other processes can also be calculated.

For the sintering process, as shown in Figure 6, the raw materials of the process mainly include quicklime, dolomite, limestone, coke, and iron ore. Among them, coke can be obtained through the coking process, and the sintered ore obtained through sintering can also be fed back to realize the input of the sintering process.

In the present invention, the amount of carbon emission in this part is less, and most of the carbon elements are counted into the sintered pellets after sintering. Therefore, in the embodiment of the present invention, it can be assumed that this process does not generate carbon emissions.

Furthermore, in the blast furnace ironmaking process, the carbon element mainly comes from coke in the coking process and sintered ore in the sintering process. In addition, additional raw materials such as anthracite can also be added. After this process, most of the raw materials generate molten iron, and a large amount of by-products such as blast furnace gas are also produced. In this process, assuming that the carbon content in the molten iron is about 4%, it can be considered that the remaining carbon elements are discharged from the molten iron through blast furnace gas. And this part of blast furnace gas, in addition to participating in recovery, the rest of the content is directly discharged through combustion to form carbon dioxide.

Therefore, the carbon emission formula under this process is E _BF =B _BF +P _BF , where B _BF is the combustion carbon emission in the blast furnace ironmaking step, and P _BF is the non-combustion carbon emission in the blast furnace ironmaking step.

在该公式中，所有输入至高炉炼铁炉中的原材料都可以被称为燃料，因此J种燃料的含量分别为Q_fuel,j，另外，EFC_fuel,j为各种燃料中的碳含量。与上文所述内容类似，这里的燃料的含量也均是反推出来的燃料含量，并非实际上所使用的燃料的量，因此，还需要增加回收的高炉煤气所导致的燃烧的碳排放量G_BF,disEFC_BPC。Specifically,

In this formula, all the raw materials input into the blast furnace ironmaking furnace can be called fuel, so the contents of J fuels are respectively Q _fuel,j , and EFC _fuel,j is the carbon content in each fuel. Similar to the content mentioned above, the fuel content here is also the calculated fuel content, not the actual amount of fuel used. Therefore, it is also necessary to increase the carbon emissions caused by the combustion of the recovered blast furnace gas G _BF,dis EFC _BPC .

In addition, a similar method can also be used to calculate the value of P _BF as P _BF =G _BF,dis EFP _BPG +G _BF,re EFP _BPG .

Carbon emissions from converter steelmaking can also be calculated after the blast furnace ironmaking step. Specifically, in this process, a small amount of carbon elements enter the molten steel, and at this time the carbon content in the molten steel is below 2.11%. Most of the carbon is collected with the converter gas into the recovery furnace. Similar to the ironmaking process, there is a part of the converter gas that is released into the air and cannot be recovered. It can be considered that the carbon element in this part of the converter gas belongs to the emission of carbon dioxide, and this part is added to the carbon emission in the recovery furnace as the non-combustion of the process. carbon emissions.

Thus, it can be obtained that E _BOF =B _BOF +P _BOF , wherein, B _BOF =Q _scrap EF _scrap +Q _hot-iron EF _hot-iron -Q hot- _steel EF _hot-steel +G _{BOF,dis EFC BOFG .} It can be understood that the carbon emission from combustion is the carbon content of the input of various raw materials minus the carbon content of the output of various raw materials. In addition, there is also the carbon emission of the vented blast furnace gas combustion. P _BOF = G _{BOF, dis} EFP _BOFG + G _{BOF, re} EFP _BOFG has carbon emissions from blast furnace gas and various recycled products caused by other non-combustion processes.

在该公式中，G_gas,re,j为第j种副产煤气的回收消耗量，EFC_gas,j则为相应的非燃烧其他工艺的排放因子。The last is the continuous casting and hot rolling process, and the carbon emission of this process can be obtained as E _roll =B _roll . There are no other non-process carbon emissions in this process, all carbon emissions are obtained by combustion,

In this formula, G _gas,re,j is the recovery consumption of the jth by-product gas, and EFC _gas,j is the emission factor of the corresponding non-combustion process.

So far, the emissions of all links can be calculated, and the carbon emissions of all links can be added together to obtain the total carbon emissions in the steelmaking process. Using a similar method, the amount of raw materials can be inferred based on the output of pig iron or steel alone, or the amount of raw materials required in each process can be estimated based on the comprehensive output of pig iron and steel, and the calculation can be performed in a cycle. Feedback the raw materials such as converter gas used, and finally solve the accurate carbon emissions.

Fig. 7 is a schematic diagram of the carbon emission ratio of each process in an embodiment of a method for measuring carbon emissions in all processes of iron and steel smelting according to the present invention. As shown in Figure 7, the proportion of carbon emissions actually produced in the above steps is roughly shown in Figure 7, in which blast furnace ironmaking will release a large amount of carbon dioxide, while other steps are relatively small, so in order to achieve a significant increase in carbon emissions The reduction should be optimized mainly from the blast furnace ironmaking step.

Fig. 8 is a schematic diagram of real-time carbon emissions changing with time in an embodiment of a method for measuring carbon emissions in all iron and steel smelting processes of the present invention. As shown in Figure 8, according to the method in the present invention, the data of carbon emissions in each month of the five years from 2016 to 2020 have been obtained. It can be seen that the carbon emissions have an increasing trend year by year, and it is obvious in summer It belongs to the season with high carbon emissions.

The beneficial effect of the present invention is that, compared with the prior art, the present invention provides a method for measuring carbon emissions in all iron and steel smelting processes. This method collects the electricity consumption data at the gate of iron and steel smelting enterprises, and obtains the relationship between the electricity consumption and the actual steel production and pig iron production, so as to estimate the iron and steel smelting process through the internal correlation between steel production and carbon emissions Real-time total carbon emissions in . The calculation process of the invention is simple, the calculation amount is very small, the calculation result is accurate, and the real-time performance is high.

The applicant of the present invention has made a detailed description and description of the implementation examples of the present invention in conjunction with the accompanying drawings, but those skilled in the art should understand that the above implementation examples are only preferred implementations of the present invention, and the detailed description is only to help readers better To understand the spirit of the present invention rather than limit the protection scope of the present invention, on the contrary, any improvement or modification made based on the spirit of the present invention shall fall within the protection scope of the present invention.

Claims (10)

1. A method for measuring carbon emissions in all processes of iron and steel smelting, characterized in that the method may further comprise the steps: Step 1. Collect the electricity consumption data, steel output and pig iron output of iron and steel smelting enterprises, and obtain the correlation between the above data based on historical data; Step 2, estimating current steel production and current pig iron production based on the association relationship and real-time power consumption at the gate; Step 3: Obtain all the processes of the iron and steel smelting enterprise in the iron and steel smelting process, and calculate the carbon emission intensity of each process, so as to obtain the real-time total carbon emission of the iron and steel smelting enterprise. 2. The method for measuring carbon emissions in all processes of iron and steel smelting according to claim 1, characterized in that: The association relationship includes a first regression equation and a second regression equation; wherein, The first regression equation is used to characterize the correlation between historical steel production and historical pig iron production; The second regression equation is used to characterize the relationship between the historical power consumption data at the gateway and the historical steel output and historical pig iron output. 3. according to the method for measuring carbon emissions in all processes of iron and steel smelting described in claim 2, characterized in that: The first regression equation X _steel is a polynomial regression equation

In the formula, X _steel (t) is the historical steel output at time t, X _iron (t) is the historical pig iron production at time t, α ₁ , α ₂ , . . . , α _n and C ₁ are coefficients of polynomials, respectively. 4. according to a kind of method for measuring carbon emissions in all iron and steel smelting processes described in claim 3, it is characterized in that: The second regression equation is a linear regression equation E _elc (t)＝C ₂ +β ₁ X _iron (t)+β ₂ X _steel (t) In the formula, E _elc (t) is the historical gate power consumption data at time t, β ₁ , β ₂ and C ₂ are coefficients of the linear equation, respectively. 5. The method for measuring carbon emissions in all processes of iron and steel smelting according to claim 4, characterized in that: All the processes mentioned above include coking process, sintering process, blast furnace ironmaking process, converter steelmaking process and continuous casting and hot rolling process; The real-time total carbon emission of the iron and steel smelting enterprise is the sum of the real-time carbon emission of each process in all the processes. 6. The method for measuring carbon emissions in all processes of iron and steel smelting according to claim 5, characterized in that: The carbon emission in the i-th process is E _process-i = B _process-i +P _process-i Among them, B _process-i is the carbon emission generated by the combustion of raw materials input into the i-th process; P _process-i is the carbon emissions generated by the raw materials input into the i-th process due to other processes other than combustion. 7. The carbon emission measurement method in all processes of iron and steel smelting according to claim 6, characterized in that: The formula for calculating the carbon emissions generated by the combustion of raw materials input into the i-th process is

Among them, j is the raw material number in the i-th process, and the value ranges from 1 to J, Q _{fuel, j} is the combustion consumption of the j-th raw material in the i-th process, EFC _{fuel, j} is the carbon content in the j-th raw material in the i-th process. 8. The method for measuring carbon emissions in all processes of iron and steel smelting according to claim 7, characterized in that: The formula for calculating the carbon emissions of raw materials input into the i-th process due to other processes other than combustion is

Among them, Q _{in-mat, j} is the input amount of j-th raw material in the i-th process, Q _{out-mat, j} is the output of the jth raw material in the i-th process, EFP _mat,j is the emission factor of non-combustion other processes of the jth raw material in the i process. 9. The method for measuring carbon emissions in all processes of iron and steel smelting according to claim 8, characterized in that: The output quantity Q _out-mat,j of the jth raw material in the ith process includes the output quantity of the jth raw material and the output quantity of the combustion product of the jth raw material. 10. The carbon emission measurement method in all processes of iron and steel smelting according to claim 9, characterized in that: The input amount Q _in-mat,j of the jth raw material in the i-th process, and the combustion consumption Q _fuel,j of the j-th raw material in the i-th process are based on the current steel output and the The current pig iron production is obtained by reverse derivation.

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