A method for calculating carbon emissions from cement production considering uncertainty factors

Abstract

The present invention discloses a method for calculating carbon emissions from cement production that takes uncertainty factors into account, and relates to the technical field of industrial carbon emission measurement. The method comprises the following steps: calculating the carbon emissions generated by raw materials during the calcination process of cement production; fitting and predicting the uncertainty factors in the complex calcination process to obtain parameter values ​​for radiant heat dissipation from the kiln surface; calculating the carbon emissions generated by fuel combustion during the calcination process of cement production based on the parameter values ​​for heat dissipation from the kiln surface; calculating the carbon emissions from electricity use during the grinding process of cement production, and then calculating the carbon emissions from cement production. When calculating the carbon emissions of raw materials, the present invention not only considers conventional carbonate decomposition, but also takes into account the impact of non-carbonate calcium oxide and organic impurities on the carbon emission calculation. Furthermore, when calculating the carbon emissions caused by fuel combustion, the method solves the problem of difficulty in evaluating uncertainty factors, thereby making the final calculation results more accurate.

Description

Technical Field

[0001] The present invention relates to the technical field of industrial carbon emission measurement, and in particular to a method for calculating carbon emissions from cement production taking uncertainty factors into consideration. Background Art

[0002] The raw materials of cement clinker are mainly limestone, sandstone, clay, slag, etc. The preparation unit grinds and screens the raw materials according to actual needs to obtain cement raw materials, mixes the prepared cement raw materials according to specifications or batching plans, and then grinds the mixed materials into powder with a mill and conveys them to the decomposition furnace equipment with an elevator for pre-decomposition. It is then calcined in a rotary kiln to obtain the burned material, which is cement clinker. Finally, it is air-cooled in a cooler and transported to the clinker warehouse with a conveyor belt for storage. The fuel for cement clinker is coal, which is stored in a separate storage bin outside the kiln. It is fed to the mill in a fixed quantity and processed into coal powder. The coal powder is then sprayed into the kiln with a pneumatic pipe as fuel for cement calcination.

[0003] As one of the many technical devices in the cement firing system, the cement rotary kiln exhibits nonlinear, multivariable, and complex calcination characteristics. Due to the high and field-distributed temperatures within the kiln, the complex movement of raw materials and fuel combustion, and the unique physical structure of the rotary kiln, the actual temperature measurement and control requirements are numerous. These issues complicate kiln temperature prediction and control. Existing carbon reduction technology routes and carbon emission calculation methods are well-defined, but they fail to consider the impact of various uncertainties on temperature during cement calcination, resulting in a lack of accurate fuel usage. This, in turn, makes it difficult to perform detailed carbon emission calculations, hindering the assessment of cement emission reduction benefits. Summary of the Invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present invention provides a method for calculating carbon emissions from cement production that takes uncertainty factors into account.

[0005] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

[0006] A method for calculating carbon emissions from cement production taking uncertainty factors into account comprises the following steps:

[0007] S1. Calculate the carbon emissions from raw meal calcination during cement production based on the required cement clinker output;

[0008] S2. Establish a cement kiln heat balance model based on the cement rotary kiln process parameters. Fit and predict the uncertainty factors in the complex calcination process based on the cement rotary kiln process parameters and production data to obtain the parameter values ​​of the cement kiln surface radiation heat dissipation;

[0009] S3. Calculate the carbon emissions generated by fuel combustion during the calcination process of cement production based on the cement kiln heat balance model in step S2 and the parameter values ​​of the cement kiln surface radiation heat dissipation;

[0010] S4. Calculate the carbon emissions from electricity use during the grinding process of cement production. Calculate the carbon emissions from cement production based on the carbon emissions from raw materials during the calcination process of cement production in step S1, the carbon emissions from fuel combustion during the calcination process of cement production in step S3, and the carbon emissions from electricity use during the grinding process of cement production.

[0011] Furthermore, step S1 includes the following steps:

[0012] S11. Calculate the amount of raw materials required based on the required cement clinker output;

[0013] S12. Determine the content of carbonate calcium oxide and non-carbonate calcium oxide in the raw materials according to the amount of the raw materials required in step S11;

[0014] S13, determining the content of organic impurities in the raw materials according to the amount of raw materials required in step S11;

[0015] S14. Calculate the carbon emissions generated by the raw materials during the calcination process of cement production based on the content of carbonate calcium oxide and non-carbonate calcium oxide in the raw materials in step S12 and the content of organic impurities in the raw materials in step S13.

[0016] Furthermore, step S14 includes the following steps:

[0017] S141. Calculate the carbon dioxide produced by decomposition of carbonates in the raw material according to the contents of carbonate calcium oxide and non-carbonate calcium oxide in the raw material in step S12, expressed as:

[0018] WHAT f =(M CaO -M n-CaO )× 44 / 56 +M MgO × 44 / 40

[0019] in: WHAT f Carbon dioxide is produced by the decomposition of carbonates in the raw material. M CaO is the mass of calcium oxide in the carbonate, M n-CaO is the mass of calcium oxide in non-carbonate salts, M MgO is the mass of magnesium oxide in the carbonate;

[0020] S142. Calculate the carbon dioxide generated during the calcination process of the organic impurities in the raw materials according to the content of organic impurities in the raw materials in step S13, expressed as:

[0021] WHAT sr =M sr ×EF sr

[0022] in: WHAT sr It is the carbon dioxide produced during the calcination process by organic impurities in the raw material. M sr is the organic impurity content in the raw materials, EF sr is the emission coefficient of organic impurities;

[0023] S143. Calculate the carbon emissions generated by the raw meal during the calcination process of cement production based on the carbon dioxide generated by the decomposition of carbonates in the raw meal in step S141 and the carbon dioxide generated by organic impurities in the raw meal during the calcination process in step S142, expressed as:

[0024] WHAT S =CE f + WHAT sr

[0025] in: WHAT S Carbon emissions from the calcination of raw materials in cement production.

[0026] Furthermore, in step S2, a cement kiln heat balance model is established according to the process parameters of the cement rotary kiln, which is expressed as:

[0027] m r ·Q net,ar +Q sr +Q s +Q k = Q sh +Q lsh +Q f +Q pk +Q B

[0028] in:m r is the fuel consumption per kilogram of clinker, Q net,ar To ensure the low calorific value of coal powder entering the kiln, Q sr The heat generated by the combustion of organic matter in the raw meal to produce one kilogram of clinker, Q s The sensible heat brought into each kilogram of clinker raw material, Q k The sensible heat of air entering the kiln for each kilogram of clinker produced, Q sh is the reaction absorption heat generated per kilogram of clinker, Q lsh The sensible heat of the clinker leaving the cooler, Q f The sensible heat of the preheater outlet gas. Q pk The sensible heat of the cooler exhaust gas. Q B Dissipate heat through radiation from the cement kiln surface.

[0029] Furthermore, in step S2, the uncertainty factors in the complex calcination process are fitted and predicted based on the process parameters and production data of the cement rotary kiln to obtain the parameter value of the radiant heat dissipation on the surface of the cement kiln, including the following steps:

[0030] A1. Based on the process parameters of cement rotary kiln, a normal distribution model of radiant heat dissipation on the surface of cement kiln is constructed, which is expressed as:

[0031] Q B ~ N ( μ 0, σ 0 2 )

[0032] in: Q B To dissipate heat through radiation from the surface of the cement kiln, N is the symbol of normal distribution, μ 0 is the expected value of radiation heat dissipation on the cement kiln surface, and the value range is determined by the process parameters of the cement rotary kiln. σ 0 is the fluctuation degree of radiant heat dissipation on the cement kiln surface;

[0033] A2. Based on the normal distribution model of the radiant heat dissipation on the cement kiln surface, the parameter values ​​of the radiant heat dissipation on the cement kiln surface are obtained using production data.

[0034] Furthermore, step A2 includes the following steps:

[0035] A21. Use production data to obtain an estimated value of the heat dissipation from the cement kiln surface and an estimated value of the fluctuation of the heat dissipation from the cement kiln surface, expressed as:

[0036]

[0037]

[0038] in: is the estimated value of the heat dissipated by radiation from the cement kiln surface, is the average value of cement kiln surface radiation heat dissipation of all samples in the production data, is the estimated value of the fluctuation degree of radiation heat dissipation on the surface of cement kiln, is the sample number in the production data, is the total number of samples in the production data, For production data Surface radiation heat dissipation of cement kilns of samples;

[0039] A22. Based on the estimated value of the radiant heat dissipation from the cement kiln surface and the estimated value of the fluctuation degree of the radiant heat dissipation from the cement kiln surface in step A21, a hypothesis test is performed on the expected value of the radiant heat dissipation from the cement kiln surface and the fluctuation degree of the radiant heat dissipation from the cement kiln surface to determine the expected value of the radiant heat dissipation from the cement kiln surface and the fluctuation degree of the radiant heat dissipation from the cement kiln surface, expressed as:

[0040] Assumptions ,have , the significance level is The rejection region of is expressed as:

[0041]

[0042] Assumptions ,have , the rejection region with significance level α is expressed as:

[0043]

[0044] in: is the first test statistic, is the sample standard deviation, The degrees of freedom are of distributed, for The probability in the distribution is The upper quantile of is the second test statistic, The degrees of freedom are of distributed, for The probability in the distribution is The upper quantile of for The probability in the distribution is The upper quantile of ;

[0045] A23. Obtain parameter values ​​of the cement kiln surface radiant heat dissipation based on the normal distribution model of the cement kiln surface radiant heat dissipation, the expected value of the cement kiln surface radiant heat dissipation in step A22, and the degree of fluctuation of the cement kiln surface radiant heat dissipation.

[0046] Furthermore, in step S3, carbon emissions generated by fuel combustion during the calcination process of cement production are calculated based on the cement kiln heat balance model in S2 and the determined radiative heat dissipation of the cement kiln surface, including the following steps:

[0047] B1. Calculate the required fuel consumption during the calcination process of cement production based on the cement kiln heat balance model;

[0048] B2. Based on the fuel consumption required for cement production during the calcination process in step B1, calculate the carbon emissions generated by fuel combustion during the calcination process of cement production, expressed as:

[0049] WHAT r =m r ·γ·44 / 12

[0050] in: WHAT r Carbon emissions from fuel combustion during the calcination process of cement production, γ is the carbon content of the fuel, and 44 / 12 is the ratio of the relative molecular mass of CO2 to C.

[0051] Furthermore, in step S4, the carbon emissions of cement production are calculated based on the carbon emissions generated by raw materials during the calcination process of cement production in step S1, the carbon emissions generated by fuel combustion during the calcination process of cement production in step S3, and the carbon emissions of electricity used during the grinding process of cement production, and are expressed as:

[0052] WHAT=WHAT e + WHAT r + WHAT S

[0053] in: WHAT Carbon emissions from cement production, WHAT e Carbon emissions from electricity use in the grinding process of cement production, WHAT r Carbon emissions from fuel combustion during the calcination process of cement production, WHATS Carbon emissions from the calcination of raw materials in cement production.

[0054] The present invention has the following beneficial effects:

[0055] (1) When calculating the carbon emissions generated by raw materials during the calcination process of cement production, the present invention calculates the amount of raw materials required based on the required cement clinker output, determines the content of carbonate calcium oxide and non-carbonate calcium oxide in the raw materials based on the required amount of raw materials, and determines the content of organic impurities in the raw materials based on the required amount of raw materials, and then calculates the carbon emissions generated by raw materials during the calcination process of cement production. In addition to considering the conventional carbonate decomposition, the influence of non-carbonate calcium oxide and organic impurities on the carbon emission calculation is also taken into account, making the calculation result more accurate;

[0056] (2) When calculating the carbon emissions generated by fuel combustion during the calcination process of cement production, the present invention establishes a cement kiln heat balance model based on the process parameters of the cement rotary kiln, and fits and predicts the uncertainty factors in the complex calcination process based on the process parameters and production data of the cement rotary kiln, obtains the parameter values ​​of the radiant heat dissipation on the surface of the cement kiln, and calculates the carbon emissions generated by fuel combustion during the calcination process of cement production based on the parameter values ​​of the radiant heat dissipation on the surface of the cement kiln and the cement kiln heat balance model. This process takes into account the complex thermal balance inside the cement kiln and the radiant heat dissipation on the surface of the cement kiln, solves the problem that the uncertainty factors affecting the temperature of the firing zone are difficult to evaluate, and thus makes the calculation results more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 A flow chart of a method for calculating carbon emissions from cement production that takes uncertainty factors into account;

[0058] Figure 2 Schematic diagram of the cement kiln heat balance model. DETAILED DESCRIPTION

[0059] The specific embodiments of the present invention are described below to facilitate understanding of the present invention by those skilled in the art. However, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the appended claims, these changes are obvious, and all inventions and creations utilizing the concepts of the present invention are protected.

[0060] like Figure 1 As shown, a method for calculating carbon emissions from cement production taking uncertainty factors into account includes steps S1-S4, which are specifically as follows:

[0061] S1. Calculate the carbon emissions from raw meal calcination during cement production based on the required cement clinker output.

[0062] In an optional embodiment of the present invention, the amount of raw materials required is calculated based on the desired cement clinker output. Raw materials for cement production primarily include limestone, silica fume, iron phase, gypsum, and magnesium carbonate, along with trace amounts of non-carbonate calcium oxide and organic impurities. Calcium carbonate and magnesium carbonate are the primary raw materials for cement. The present invention calculates the amount of calcium carbonate and magnesium carbonate required based on the desired cement clinker output to calculate the required raw material amounts, thereby calculating the carbon emissions generated by the raw meal during the cement production calcination process.

[0063] Step S1 includes the following steps:

[0064] S11. Calculate the amount of raw materials required based on the required cement clinker output.

[0065] The present invention calculates the dosage of calcium carbonate and magnesium carbonate according to the required cement clinker output, so as to calculate the dosage of the required raw materials.

[0066] The present invention calculates the consumption of calcium carbonate, and is expressed as:

[0067] ,

[0068]

[0069] in: is the dosage of calcium carbonate, The calcium carbonate consumed to generate C3S, Calcium carbonate consumed to generate C2S, The calcium carbonate consumed to generate C3A, The calcium carbonate consumed to generate C4AF, To generate C4A3 The amount of calcium carbonate consumed, Calcium carbonate consumed to generate f-CaO. To generate Calcium carbonate consumed by clinker-like components, They represent C3S, C2S, C3A, C4AF, C4A3S and f-CaO respectively. is the proportion of the i-th mineral component in the clinker, It is the ratio of the mass of CaCO3 involved in the chemical reaction to produce 1 mol of mineral to the molar mass of the mineral in the clinker.

[0070] The present invention calculates the consumption of magnesium carbonate, and is expressed as:

[0071]

[0072] in: is the dosage of magnesium carbonate, It is the proportion of MgO in clinker.

[0073] S12. Determine the content of carbonate calcium oxide and non-carbonate calcium oxide in the raw materials according to the amount of raw materials required in step S11.

[0074] The present invention adopts chemical methods such as glycerol method and ethylene glycol method according to the amount of required raw materials to determine the content of carbonate calcium oxide and non-carbonate calcium oxide in the raw materials.

[0075] S13. Determine the content of organic impurities in the raw materials according to the amount of raw materials required in step S11.

[0076] S14. Calculate the carbon emissions generated by the raw materials during the calcination process of cement production based on the content of carbonate calcium oxide and non-carbonate calcium oxide in the raw materials in step S12 and the content of organic impurities in the raw materials in step S13.

[0077] Step S14 includes the following steps:

[0078] S141. Calculate the carbon dioxide produced by decomposition of carbonates in the raw material according to the contents of carbonate calcium oxide and non-carbonate calcium oxide in the raw material in step S12, expressed as:

[0079] WHAT f =(M CaO -M n-CaO )× 44 / 56 +M MgO × 44 / 40

[0080] in: WHAT f Carbon dioxide is produced by the decomposition of carbonates in the raw material. M CaO is the mass of calcium oxide in the carbonate, M n-CaO is the mass of calcium oxide in non-carbonate salts, M MgO is the mass of magnesium oxide in carbonate.

[0081] S142. Calculate the carbon dioxide generated during the calcination process of the organic impurities in the raw materials according to the content of organic impurities in the raw materials in step S13, expressed as:

[0082] WHAT sr =M sr ×EF sr

[0083] in: WHAT sr It is the carbon dioxide produced during the calcination process by organic impurities in the raw material. M sr is the organic impurity content in the raw materials, EF sr is the emission coefficient of organic impurities.

[0084] S143. Calculate the carbon emissions generated by the raw meal during the calcination process of cement production based on the carbon dioxide generated by the decomposition of carbonates in the raw meal in step S141 and the carbon dioxide generated by organic impurities in the raw meal during the calcination process in step S142, expressed as:

[0085] WHAT S =CE f + WHAT sr

[0086] in: WHAT S Carbon emissions from the calcination of raw materials in cement production.

[0087] S2. Based on the process parameters of the cement rotary kiln, a cement kiln heat balance model is established. The uncertainty factors in the complex calcination process are fitted and predicted based on the process parameters and production data of the cement rotary kiln to obtain the parameter values ​​of the cement kiln surface radiation heat dissipation.

[0088] In an optional embodiment of the present invention, the uncertainty factors include the complex heat balance inside the cement kiln and the radiation heat dissipation on the surface of the cement kiln.

[0089] like Figure 2 As shown, the present invention takes into account the energy balance of the firing system and establishes a cement kiln heat balance model taking into account uncertainty factors, which is expressed as:

[0090] m r ·Q net,ar +Q sr +Q s +Q k = Q sh +Q lsh +Q f +Q pk +Q B

[0091] in: m r is the fuel consumption per kilogram of clinker, Q net,ar To ensure the low calorific value of coal powder entering the kiln, Q sr The heat generated by the combustion of organic matter in the raw meal to produce one kilogram of clinker, Q s The sensible heat brought into each kilogram of clinker raw material, Q k The sensible heat of air entering the kiln for each kilogram of clinker produced, Q sh is the reaction absorption heat generated per kilogram of clinker, Q lsh The sensible heat of the clinker leaving the cooler, Q f The sensible heat of the preheater outlet gas. Q pk The sensible heat of the cooler exhaust gas. Q B Dissipate heat through radiation from the cement kiln surface.

[0092] The present invention calculates the heat Q generated by fuel combustion when producing each kilogram of clinker rR , expressed as:

[0093] Q rR =m r ·Q net,ar

[0094] in: m r The mass of fuel required to produce each kilogram of clinker, Q net,ar The fuel receives a low calorific value.

[0095] The present invention calculates the heat generated by the combustion of organic matter in the raw material when producing each kilogram of clinker Q sr , expressed as:

[0096] Q sr =m sr ·Q net,sr

[0097] in: m sr The amount of organic impurities in each kilogram of clinker raw material produced, Q net,sr The organic impurities receive a low-level heat.

[0098] The present invention calculates the sensible heat brought into each kilogram of clinker raw material Q s , expressed as:

[0099] Q s = m s · c s · t s，

[0100]

[0101] in: m s is the mass of raw material per kilogram of clinker, c s is the specific heat capacity of the raw material, is the moisture content of raw material, t s is the temperature of the raw material.

[0102] The present invention calculates the sensible heat of air entering the kiln per kilogram of clinker produced Q k , expressed as:

[0103] Q k = m k · c k · t k

[0104] in: m k is the mass of air entering the kiln per kilogram of clinker, c k is the specific heat capacity of the air entering the kiln, t k is the ambient temperature of the air entering the kiln.

[0105] The present invention calculates the reaction absorption heat generated per kilogram of clinker Q sh , expressed as:

[0106] Q sh =Σ( m k · )+Σ( w x · )

[0107] in: mk is the consumption of raw materials, for k Enthalpy change of conversion to oxides, w x Clinker phase in clinker x quality, For oxides and CaSO 4Generate x enthalpy change.

[0108] The present invention calculates the sensible heat of cooler clinker Q lsh , expressed as:

[0109] Q lsh = m lsh · c lsh · t lsh

[0110] in: m lsh is the mass of clinker out of the cooler per kilogram of clinker, c lsh is the specific heat capacity of clinker, t lsh It is the ambient temperature of clinker leaving the cooler.

[0111] The present invention calculates the sensible heat of the preheater outlet gas Q f , expressed as:

[0112] Q f =V f / M sh ·c f ·t f，

[0113]

[0114] in: V f is the exhaust gas volume at the preheater outlet per hour, M sh is the hourly clinker production, t f is the temperature of the exhaust gas at the preheater outlet, c f is the volumetric specific heat capacity of the exhaust gas at the preheater outlet, is the mass weight of CO2 in the mixed gas, is the volume specific heat capacity of CO2, is the mass weight of CO in the mixed gas, is the volumetric specific heat capacity of CO, is the mass weight of O2 in the mixed gas, is the volume specific heat capacity of O2, is the mass weight of N2 in the mixed gas, is the volume specific heat capacity of N2, is the mass weight of H2O in the mixed gas, is the volume specific heat capacity of H2O.

[0115] The present invention calculates the sensible heat of the cooling machine outlet gas Q pk , expressed as:

[0116] Q pk =V pk / M pk ·c pk ·t pk

[0117] in: V pk is the volume of air discharged from the cooler per hour, M pk is the hourly clinker production, c pk is the specific heat capacity of the cooler outlet gas volume, t pk The temperature of the cooler outlet air.

[0118] The present invention fits and predicts the uncertainty factors in the complex calcination process based on the process parameters and production data of the cement rotary kiln, and obtains the parameter value of the radiation heat dissipation on the surface of the cement kiln, including the following steps:

[0119] A1. Based on the process parameters of cement rotary kiln, a normal distribution model of radiant heat dissipation on the surface of cement kiln is constructed, which is expressed as:

[0120] Q B ~ N ( μ 0, σ 0 2 )

[0121] in: Q B To dissipate heat through radiation from the surface of the cement kiln, N is the symbol of normal distribution, μ0 is the expected value of radiation heat dissipation on the cement kiln surface, and the value range is determined by the process parameters of the cement rotary kiln. σ 0 is the fluctuation degree of radiation heat dissipation on the surface of cement kiln.

[0122] Conventional cement rotary kilns can produce 5×10 6 kg clinker, radius 2.4m, length 74m. According to the process parameters of cement rotary kiln, the present invention determines that the radiation heat dissipation range of rotary kiln is 150kj / kg~300kj / kg, so there are 150 <μ 0 <300 .

[0123] A2. Based on the normal distribution model of the radiant heat dissipation on the cement kiln surface, the parameter values ​​of the radiant heat dissipation on the cement kiln surface are obtained using production data.

[0124] Step A2 includes the following steps:

[0125] A21. Use production data to obtain an estimated value of the heat dissipation from the cement kiln surface and an estimated value of the fluctuation of the heat dissipation from the cement kiln surface, expressed as:

[0126]

[0127]

[0128] in: is the estimated value of the heat dissipated by radiation from the cement kiln surface, is the average value of cement kiln surface radiation heat dissipation of all samples in the production data, is the estimated value of the fluctuation degree of radiation heat dissipation on the surface of cement kiln, is the sample number in the production data, is the total number of samples in the production data, For production data Surface radiation heat dissipation of cement kilns of samples.

[0129] A22. Based on the estimated value of the radiant heat dissipation from the cement kiln surface and the estimated value of the fluctuation degree of the radiant heat dissipation from the cement kiln surface in step A21, a hypothesis test is performed on the expected value of the radiant heat dissipation from the cement kiln surface and the fluctuation degree of the radiant heat dissipation from the cement kiln surface to determine the expected value of the radiant heat dissipation from the cement kiln surface and the fluctuation degree of the radiant heat dissipation from the cement kiln surface, expressed as:

[0130] Assumptions ,have , the significance level is The rejection region of is expressed as:

[0131]

[0132] Assumptions ,have , the rejection region with significance level α is expressed as:

[0133]

[0134] in: is the first test statistic, is the sample standard deviation, The degrees of freedom are of distributed, for The probability in the distribution is The upper quantile of is the second test statistic, The degrees of freedom are of distributed, for The probability in the distribution is The upper quantile of for The probability in the distribution is The upper quantile of ;

[0135] A23. Obtain parameter values ​​of the cement kiln surface radiant heat dissipation based on the normal distribution model of the cement kiln surface radiant heat dissipation, the expected value of the cement kiln surface radiant heat dissipation in step A22, and the degree of fluctuation of the cement kiln surface radiant heat dissipation.

[0136] S3. Calculate the carbon emissions generated by fuel combustion during the calcination process of cement production based on the cement kiln heat balance model in step S2 and the parameter values ​​of the cement kiln surface radiation heat dissipation.

[0137] In an optional embodiment of the present invention, the present invention calculates carbon emissions generated by fuel combustion during the calcination process of cement production based on a cement kiln heat balance model, including the following steps:

[0138] B1. Calculate the amount of fuel required for cement production during the calcination process based on the cement kiln heat balance model.

[0139] B2. Based on the fuel consumption required for cement production during the calcination process in step B1, calculate the carbon emissions generated by fuel combustion during the calcination process of cement production, expressed as:

[0140] WHAT r =m r ·γ·44 / 12

[0141] in: WHAT rCarbon emissions from fuel combustion during the calcination process of cement production, γ is the carbon content of the fuel, and 44 / 12 is the ratio of the relative molecular mass of CO2 to C.

[0142] S4. Calculate the carbon emissions from electricity use during the grinding process of cement production. Calculate the carbon emissions from cement production based on the carbon emissions from raw materials during the calcination process of cement production in step S1, the carbon emissions from fuel combustion during the calcination process of cement production in step S3, and the carbon emissions from electricity use during the grinding process of cement production.

[0143] In an optional embodiment of the present invention, the present invention calculates the carbon emissions of electricity used in the grinding process of cement production, which is expressed as:

[0144] WHAT e =E×EF e

[0145] in: WHAT e Carbon emissions from electricity use in the grinding process of cement production, E For electricity consumption, EF e is the CO2 emission factor for electricity production.

[0146] The present invention calculates the carbon emissions of cement production based on the carbon emissions generated by raw materials during the calcination process of cement production in step S1, the carbon emissions generated by fuel combustion during the calcination process of cement production in step S3, and the carbon emissions of electricity used during the grinding process of cement production, which can be expressed as:

[0147] WHAT=WHAT e + WHAT r + WHAT S

[0148] in: WHAT Carbon emissions from cement production, WHAT e Carbon emissions from electricity use in the grinding process of cement production, WHAT r Carbon emissions from fuel combustion during the calcination process of cement production, WHAT S Carbon emissions from the calcination of raw materials in cement production.

[0149] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts 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, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0150] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0151] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0152] Specific embodiments are used in the present invention to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

[0153] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and it should be understood that the scope of protection of the present invention is not limited to such specific descriptions and embodiments. Those skilled in the art can make various other specific variations and combinations based on the technical teachings disclosed in the present invention without departing from the essence of the present invention, and such variations and combinations are still within the scope of protection of the present invention.

Claims

1. A method for calculating carbon emissions from cement production taking into account uncertainty factors, characterized in that: The following steps are involved: S1. Calculate the carbon emissions from raw meal calcination during cement production based on the required cement clinker output; S2. Establish a thermal balance model for the cement rotary kiln based on the process parameters of the cement rotary kiln. Fit and predict the uncertainty factors in the complex calcination process based on the process parameters and production data of the cement rotary kiln to obtain the parameter value of the surface radiation heat dissipation of the cement rotary kiln. Uncertain factors include the complex heat balance inside the cement rotary kiln and the radiation heat dissipation on the surface of the cement rotary kiln; According to the process parameters of cement rotary kiln, the heat balance model of cement rotary kiln is established, which is expressed as: m r ·Q net,ar +Q sr +Q s +Q k =Q sh +Q lsh +Q f +Q pk +Q B Where: m r is the fuel consumption per kilogram of clinker, Q net,ar The coal powder entering the kiln receives the lowest calorific value, Q sr Q is the heat generated by the combustion of organic matter in the raw meal to produce one kilogram of clinker, s is the sensible heat brought into the raw material per kilogram of clinker, Q k Q is the sensible heat of air entering the kiln per kilogram of clinker produced, sh Q is the heat of reaction absorbed per kilogram of clinker, lsh is the sensible heat of clinker leaving the cooler, Q f is the sensible heat of the preheater outlet gas, Q pk is the sensible heat of the cooler exhaust, Q B Dissipate heat through radiation from the surface of cement rotary kiln; The uncertainty factors in the complex calcination process are fitted and predicted based on the process parameters and production data of the cement rotary kiln to obtain the parameter values ​​of the surface radiation heat dissipation of the cement rotary kiln, including the following steps: A1. Based on the process parameters of cement rotary kiln, a normal distribution model of surface radiation heat dissipation of cement rotary kiln is constructed, which is expressed as: Q B ~N(μ0,σ0 2 ) Where: Q B is the surface radiation heat dissipation of the cement rotary kiln, N is the symbol of normal distribution, μ0 is the expected value of the surface radiation heat dissipation of the cement rotary kiln, the value range is determined by the process parameters of the cement rotary kiln, and σ0 is the fluctuation degree of the surface radiation heat dissipation of the cement rotary kiln; A2. Based on the normal distribution model of the heat dissipation by radiation from the surface of the cement rotary kiln, the parameter values ​​of the heat dissipation by radiation from the surface of the cement rotary kiln are obtained using production data; Step A2 includes the following steps: A21. Use production data to obtain an estimated value of the heat dissipation from the cement rotary kiln surface and an estimated value of the fluctuation of the heat dissipation from the cement rotary kiln surface, expressed as: Where: μ is the estimated value of radiation heat dissipation on the surface of cement rotary kiln, is the average radiation heat dissipation of the cement rotary kiln surface of all samples in the production data, σ is the estimated value of the fluctuation degree of radiation heat dissipation of the water rotary kiln surface, i is the sample number in the production data, n is the total number of samples in the production data, X i is the surface radiation heat dissipation of the cement rotary kiln of the i-th sample in the production data; A22. Based on the estimated value of the heat dissipation by radiation from the cement rotary kiln surface and the estimated value of the degree of fluctuation of the heat dissipation by radiation from the cement rotary kiln surface in step A21, a hypothesis test is performed on the expected value of the heat dissipation by radiation from the cement rotary kiln surface and the degree of fluctuation of the heat dissipation by radiation from the cement rotary kiln surface to determine the expected value of the heat dissipation by radiation from the cement rotary kiln surface and the degree of fluctuation of the heat dissipation by radiation from the cement rotary kiln surface, which is expressed as: Assuming μ=μ0, we have The rejection region with a significance level of α is expressed as: Assumptions have The rejection region with a significance level of α is expressed as: Where: T is the first test statistic, S* is the sample standard deviation, t(n-1) is the t distribution with (n-1) degrees of freedom, The probability in the t distribution is The upper quantile of X 2 is the second test statistic, X 2 (n) is X with n degrees of freedom 2 distributed, For X 2 The probability in the distribution is The upper quantile of For X 2 The probability in the distribution is The upper quantile of ; A23. Obtaining parameter values ​​of the radiant heat dissipation of the cement rotary kiln surface based on the normal distribution model of the radiant heat dissipation of the cement rotary kiln surface, the expected value of the radiant heat dissipation of the cement rotary kiln surface in step A22, and the degree of fluctuation of the radiant heat dissipation of the cement rotary kiln surface; S3, calculating the carbon emissions generated by fuel combustion during the calcination process of cement production based on the cement rotary kiln heat balance model and the parameter values ​​of the cement rotary kiln surface radiation heat dissipation in step S2; S4. Calculate the carbon emissions from electricity use during the grinding process of cement production. Calculate the carbon emissions from cement production based on the carbon emissions from raw materials during the calcination process of cement production in step S1, the carbon emissions from fuel combustion during the calcination process of cement production in step S3, and the carbon emissions from electricity use during the grinding process of cement production.

2. The method for calculating carbon emissions from cement production taking uncertainty factors into account according to claim 1, characterized in that: Step S1 includes the following steps: S11. Calculate the amount of raw materials required based on the required cement clinker output; S12. Determine the content of carbonate calcium oxide and non-carbonate calcium oxide in the raw materials according to the amount of the raw materials required in step S11; S13, determining the content of organic impurities in the raw materials according to the amount of raw materials required in step S11; S14. Calculate the carbon emissions generated by the raw materials during the calcination process of cement production based on the content of carbonate calcium oxide and non-carbonate calcium oxide in the raw materials in step S12 and the content of organic impurities in the raw materials in step S13.

3. The method for calculating carbon emissions from cement production taking uncertainty factors into account according to claim 2, characterized in that: Step S14 includes the following steps: S141. Calculate the carbon dioxide produced by decomposition of carbonates in the raw material according to the contents of carbonate calcium oxide and non-carbonate calcium oxide in the raw material in step S12, expressed as: WHAT f =(M CaO -M n-CaO )×44 / 56+M MgO ×44 / 40 Among them: CE f M is the carbon dioxide produced by the decomposition of carbonates in the raw material. CaO is the mass of calcium oxide in carbonate, M n-CaO is the mass of calcium oxide in non-carbonate, M MgO is the mass of magnesium oxide in carbonate; S142. Calculate the carbon dioxide generated during the calcination process of the organic impurities in the raw materials according to the content of organic impurities in the raw materials in step S13, expressed as: WHAT sr =M sr ×EF sr Among them: CE sr M is the carbon dioxide produced during the calcination process by organic impurities in the raw material. sr is the organic impurity content in the raw materials, EF sr is the emission coefficient of organic impurities; S143. Calculate the carbon emissions generated by the raw meal during the calcination process of cement production based on the carbon dioxide generated by the decomposition of carbonates in the raw meal in step S141 and the carbon dioxide generated by organic impurities in the raw meal during the calcination process in step S142, expressed as: WHAT S =EC f +CE sr Among them: CE S Carbon emissions from the calcination of raw materials in cement production.

4. The method for calculating carbon emissions from cement production considering uncertainty factors according to claim 1, characterized in that: In step S3, carbon emissions generated by fuel combustion during the calcination process of cement production are calculated based on the cement rotary kiln heat balance model in S2 and the determined surface radiation heat dissipation of the cement rotary kiln, including the following steps: B1. Calculate the required fuel consumption during the calcination process of cement production based on the cement rotary kiln heat balance model; B2. Based on the fuel consumption required for cement production during the calcination process in step B1, calculate the carbon emissions generated by fuel combustion during the calcination process of cement production, expressed as: WHAT r =m r ·γ·44 / 12 Among them: CE r is the carbon emission generated by fuel combustion during the calcination process of cement production, γ is the carbon content of the fuel, and 44 / 12 is the ratio of the relative molecular mass of CO2 to C.

5. The method for calculating carbon emissions from cement production considering uncertainty factors according to claim 1, characterized in that: In step S4, the carbon emissions of cement production are calculated based on the carbon emissions generated by raw materials during the calcination process of cement production in step S1, the carbon emissions generated by fuel combustion during the calcination process of cement production in step S3, and the carbon emissions of electricity used during the grinding process of cement production. It is expressed as: WHAT=WHAT e +CE r +CE S Among them: CE is the carbon emission from cement production, CE e Carbon emissions from electricity use in the grinding process of cement production, CE r Carbon emissions from fuel combustion during the calcination process of cement production, CE S Carbon emissions from the calcination of raw materials in cement production.

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