A method for calculating kinetic energy of blast furnace blast

Abstract

The present invention relates to a method for calculating blast furnace kinetic energy, and belongs to the technical field of blast furnace ironmaking in the metallurgical industry. The technical scheme is: operate according to the following steps: the first step: determine and calculate the carbon combustion rate; the second step: determine the oxygen consumption per ton of iron and the blast oxygen consumption per ton of iron; the third step: calculate the comprehensive air volume entering the furnace; the fourth step: calculate the blast kinetic energy, blast kinetic energy = 1 / 2*(comprehensive air volume entering the furnace / 60 / number of air ports)*blast severity / 9.8*((comprehensive air volume entering the furnace / 60 / air inlet area)*((hot air temperature+273) / 273)*(100 / (hot air pressure+100)))^2; wherein: blast kinetic energy, unit, kg.m / s; air inlet area, unit, m 2 ; Hot blast temperature, unit, °C; Hot blast pressure, unit, KPa. The beneficial effects of the present invention are: it can accurately calculate the comprehensive air volume entering and exiting the furnace and the blast kinetic energy, and provide a basis for blast furnace strengthening.

Description

Technical Field

[0001] The invention relates to a method for calculating blast furnace blast kinetic energy, and belongs to the technical field of blast furnace ironmaking in the metallurgical industry. Background Art

[0002] Blast furnace blast kinetic energy is a very important parameter in the blast furnace smelting process. Appropriate blast kinetic energy is conducive to the activity of the furnace and the stability of the furnace condition. Different blast furnace capacities and raw material conditions have corresponding blast kinetic energy. According to blast furnace smelting knowledge, blast kinetic energy = 1 / 2*(comprehensive air volume into the furnace / 60 / number of tuyere)*blast density / 9.8*((comprehensive air volume into the furnace / 60 / air inlet area)*(((hot air temperature+273) / 273)*(standard atmospheric pressure / (hot air pressure+standard atmospheric pressure)))^2 =comprehensive air volume into the furnace^3 / number of tuyere / air inlet area^2*((hot air temperature+273) / (hot air pressure+100))^2*(0.5 / 60*1.304 / 9.8*100^2 / 273^2), which involves five variable parameters such as the comprehensive air volume entering the furnace, the number of tuyere, the air inlet area, the hot air temperature, and the hot air pressure. Since the four parameters of the number of tuyere, the air inlet area, the hot air temperature, and the hot air pressure are determined and accurate, and the comprehensive air volume entering the furnace is large, the pipeline measurement error is large, and the formula is a cubic relationship, it has the greatest impact on the calculation of the blast kinetic energy. Therefore, only by accurately measuring the comprehensive air volume entering the furnace can the blast kinetic energy be accurately calculated. The comprehensive air volume entering the furnace has always been mainly measured by pipeline differential pressure measurement and temperature compensation, but due to the influence of various factors such as the measurement position of the air volume meter, the direction of the pipeline, and the error of the air volume meter itself, the measured comprehensive air volume entering the furnace varies greatly for blast furnaces with similar furnace capacity, similar raw material conditions, and similar smelting intensity, and there is no convincing standard.

[0003] Therefore, if there is a more accurate method for calculating blast kinetic energy, the blast kinetic energy calculated from the air volume measured by a conventional air volume meter can be verified and compared, thereby obtaining the accurate blast kinetic energy and providing a basis for blast furnace strengthening. Summary of the invention

[0004] The purpose of the present invention is to provide a method for calculating the blast furnace blast kinetic energy, which can accurately calculate the comprehensive air volume entering the furnace and the blast kinetic energy, provide a basis for blast furnace strengthening, and solve the problems existing in the background technology.

[0005] The technical solution of the present invention is:

[0006] A method for calculating the kinetic energy of blast furnace blast is operated according to the following steps:

[0007] Step 1: Determine and calculate the carbon combustion rate

[0008] The calculation based on the carbon balance principle of blast furnace smelting law is as follows:

[0009] (a) Calculation of gasified carbon

[0010] According to C f =C g + C C =C b +C d +C c , C f =K*C K + M*C m , R = K + M, we know that C g = C f - C C = K*C K + M*C m -C C .in:

[0011] C f , Carbon ratio refers to the amount of carbon entering the furnace, unit, kg / t;

[0012] R, fuel ratio, unit, kg / t;

[0013] K, coke ratio, unit, kg / t;

[0014] M, coal ratio, unit, kg / t;

[0015] C K , mass percentage of fixed carbon in coke, unit, %;

[0016] C m , fixed carbon mass percentage of PCI coal, unit, %;

[0017] C g , gasification carbon content, unit, kg / t;

[0018] C b , refers to the amount of carbon burned before the tuyere, unit, kg / t;

[0019] C C , carburized amount in pig iron, unit, kg / t;

[0020] C d , Carbon consumption by direct reduction, unit, kg / t;

[0021] (b) Calculation of carbon combustion rate before tuyere

[0022] The amount of carbon burned before the tuyere = the amount of carbon burned by the oxygen in the blast + the amount of carbon consumed by the oxygen in the injected coal

[0023] C b = Cg / 12*22.4 / (CO+ CO2)*(N2 / N 2b )*O 2b *24 / 22.4+M*O 2m / 32*24

[0024] = 2*C g *N2 / (CO+ CO2)*(O 2b / N 2b )+ M*O 2m / 32*24

[0025] =2*N2 / (CO+ CO2)*(O 2b / N 2b )*(C f -C C )+ M*O 2m / 32*24

[0026] =2*N2 / (CO+ CO2)*(O 2b / N 2b )*(K*C K + M*C m -C C )+ M*O 2m / 32*24

[0027] C φ =C b / C f =2*N2 / (CO+ CO2)*(O 2b / N 2b )*(K*C K +M*C m -C C ) / C f +(M*O 2m / 32*24) / C f

[0028] =2*N2 / (CO+ CO2)*(O 2b / N 2b )*(1-C C / C f )+(M*O 2m / 32*24) / C f

[0029] in:

[0030] C φ , carbon combustion rate before the tuyere, unit, %;

[0031] O 2m, the mass percentage of oxygen in the injected coal, constant value, 8%;

[0032] O 2b , volume percentage of blast oxygen, unit, %;

[0033] N 2b , volume percentage of blast nitrogen, unit, %;

[0034] CO, CO2, H2, N2 refer to the volume percentage of the top gas components, unit, %; CO+CO2+H2+N2=100%;

[0035] Step 2: Determine oxygen consumption per ton of iron and blast oxygen consumption per ton of iron

[0036] According to the known equation "oxygen consumption per ton of iron = oxygen consumption per ton of iron in blast air + oxygen consumption per ton of iron in coal injection", we can know that:

[0037] Blast oxygen consumption per ton of iron = oxygen consumption per ton of iron - oxygen content in injected coal per ton of iron = carbon ratio * carbon combustion rate / 24 * 22.4 - coal ratio * 8% / 32 * 22.4; where:

[0038] Oxygen consumption per ton of iron, oxygen consumption in blast air per ton of iron, oxygen content in coal injection per ton of iron, all in m 3 / t;

[0039] Step 3: Calculate the comprehensive air volume entering the furnace

[0040] (a) Hourly oxygen volume

[0041] Hourly oxygen volume = ton iron consumption oxygen volume * theoretical iron volume for the whole day / 24

[0042] Among them: theoretical iron content for the whole day, unit, t / d; oxygen content of the hourly blast, unit, m 3 / h;

[0043] (b) Air volume into furnace

[0044] According to the two known equations, "blast oxygen content + blast nitrogen content = 1" and "blast oxygen content = 0.21 + 0.29 * artificial humidity + 0.79 * oxygen rate"; where: 0.21, oxygen content in the atmosphere, constant; artificial humidity, the proportion of artificial humidification volume flow to the comprehensive air volume entering the furnace; oxygen rate, the proportion of oxygen-enriched volume to the comprehensive air volume entering the furnace; it can be known that:

[0045] Air volume into furnace = ((hourly blast oxygen volume - artificial humidification mass flow rate / 0.804 * (blast oxygen content - 0.21)) * (0.79 - (blast oxygen content - 0.21)) + (0.29 - (blast oxygen content - 0.21)) * hourly blast oxygen volume / 0.804) / (0.21 * (0.79 - (blast oxygen content - 0.21)) + (blast oxygen content - 0.21)) / 60;

[0046] Oxygen enrichment = hourly blast oxygen volume - furnace air volume * 60 * 0.21 - artificial humidification mass flow / 0.804 * 0.5;

[0047] Where: 0.804, constant, density of water vapor under standard conditions, 18 / 22.4=0.804, unit kg / m 3 ;

[0048] (c) Comprehensive air volume into the furnace

[0049] Comprehensive air volume into the furnace = air volume into the furnace + oxygen enrichment / 60 + artificial humidification mass flow / 60 / 0.804; where:

[0050] The air volume entering the furnace refers to the pure air volume entering the furnace, excluding the oxygen enrichment volume and artificial humidification mass flow rate, unit, m 3 / min;

[0051] Comprehensive air volume into the furnace, unit, m 3 / min;

[0052] Oxygen enrichment, unit, m 3 / h;

[0053] Artificial humidification mass flow rate, unit, kg / h;

[0054] Step 4: Calculate the kinetic energy of the wind

[0055] Blast kinetic energy = 1 / 2*(comprehensive air volume into the furnace / 60 / number of tuyere)*blast severity / 9.8*((comprehensive air volume into the furnace / 60 / air inlet area)*((hot air temperature+273) / 273)*(100 / (hot air pressure+100)))^2;

[0056] Among them: kinetic energy of air blowing, unit, kg.m / s; number of air outlets, unit, piece; air inlet area, unit, m 2 ; Blast weight, constant, 1.304, unit, kg / m 3 ; Hot air temperature, unit, ℃; Hot air pressure, unit, KPa.

[0057] The artificial humidification mass flow rate in the third step is zero when the blast furnace is in normal production and no artificial humidification is required; when the blast furnace is in abnormal condition, artificial humidification is required to restore the condition, unit, kg / h.

[0058] The beneficial effects of the present invention are:

[0059] (1) The present invention provides a general formula for calculating the carbon combustion rate before the tuyere. The carbon combustion rate calculated by this formula not only takes into account the carbon amount burned by oxygen in the blast, but also takes into account the carbon amount consumed by oxygen in the injected coal. Therefore, the calculated carbon combustion rate is relatively accurate. In addition, once the accurate carbon combustion rate is obtained, the oxygen consumption per ton of iron and the oxygen consumption per ton of iron can be calculated according to the carbon ratio, and then the comprehensive air volume entering the furnace and the kinetic energy of the blast can be calculated;

[0060] (2) The present invention can calculate the carbon combustion rate before the tuyere based on parameters such as carbon ratio, top gas composition, blast composition, and pig iron carburization amount; the blast oxygen consumption per ton of iron can be calculated based on the equation "oxygen consumption per ton of iron = blast oxygen consumption per ton of iron + oxygen content in injected coal per ton of iron". The inlet air volume, oxygen enrichment, and inlet comprehensive air volume can be calculated based on the theoretical iron content for the whole day and the two equations "blast oxygen content + blast nitrogen content = 1" and "blast oxygen content = 0.21 + 0.29 * artificial humidity + 0.79 * oxygen consumption rate". Finally, the accurate blast kinetic energy can be calculated based on the known parameters such as the number of tuyere, air inlet area, hot air temperature, and hot air pressure.

[0061] (3) The comprehensive air volume and blast kinetic energy calculated by the present invention are highly accurate, and can verify and compare the blast kinetic energy calculated by the air volume measured by a conventional air volume meter, which is a useful and important supplement to the direct calculation of the blast kinetic energy by conventional air volume meter measurement. In addition, with accurate blast kinetic energy, the difference in blast kinetic energy under similar furnace capacity, similar raw material conditions, and similar smelting intensity can be compared, thereby providing a basis for adjusting and optimizing blast furnace operation. DETAILED DESCRIPTION

[0062] Example 1: Taking a blast furnace as an example, the steps for calculating the blast kinetic energy are specifically introduced:

[0063] The first step is to determine and calculate the carbon combustion rate

[0064] (a) Calculation of gasified carbon

[0065] Given: K = 385kg / t, M = 145kg / t, C K =87%, C m =72%, C C =45kg / t, it can be seen that

[0066] C g = Cf - C C = K*C K + M*C m - C C =385*87%+145*72%-45=439.4-45=394.4kg / t

[0067] (b) Calculation of carbon combustion rate before tuyere

[0068] It is known that the mass percentage of oxygen in the injected coal, O 2m =8%, fixed value;

[0069] Blast oxygen and nitrogen content, O 2b =0.24, N 2b =0.76, O 2b +N 2b =0.24+0.76=1;

[0070] The composition of furnace top gas is CO2=20.5%, CO=25%, H2=2.5%, N2=52.0%, CO2+CO+ H2+N2=20.5%+25%+2.5%+52.0%=100%.

[0071] The amount of carbon burned before the tuyere = the amount of carbon burned by the blast oxygen + the amount of carbon consumed by the oxygen in the injected coal

[0072] C b = 2*N2 / (CO2+CO)*O 2b / N 2b *(C f -C C )+ M*O 2m / 32*24

[0073] =2*N2 / (CO2+CO)*O 2b / N 2b *(K*C K + M*C m -C C )+ M*O 2m / 32*24

[0074] =2*N2 / (CO2+CO)*O 2b / N 2b *C g + M*O 2m / 32*24

[0075] =2*52.0% / (20.5%+25%)*0.24 / 0.76*394.4+(145*8%*24 / 32)

[0076] =284.7+8.7=293.4kg / t

[0077] C φ = C b / C f =284.7 / 439.4+8.7 / 439.4=0.65+0.02=0.67

[0078] From the calculation formula, we can know the factors affecting carbon combustion rate:

[0079] (a) The greater the oxygen enrichment rate, the greater the blast oxygen content, and the greater the carbon combustion rate before the tuyere. And vice versa;

[0080] (b) In the early stage of blast furnace overhaul and repair, the furnace heat is low, the air volume is small, the total oxygen content of the blast is small, the carbon combustion rate is low, and a higher fuel ratio is required to provide heat;

[0081] (c) The amount of carbon burned before the tuyere is composed of the amount of carbon burned by the blast oxygen and the amount of carbon consumed by the oxygen in the injected coal. Although the amount of carbon consumed by the oxygen in the injected coal is small, it cannot be ignored because the carbon combustion rate before the tuyere calculated by it is a coefficient, and the carbon combustion rate is a multiple relationship to the calculation of the subsequent furnace air volume;

[0082] (d) According to multiple calculation cases, the normal range of carbon combustion rate before the tuyere is 0.65-0.70. When using the carbon combustion rate for calculation, the average value of 0.67 can be taken;

[0083] The second step is to determine the oxygen consumption per ton of iron and the blast oxygen consumption per ton of iron

[0084] Blast oxygen consumption per ton of iron = oxygen consumption per ton of iron - oxygen content in injected coal per ton of iron = carbon ratio * carbon combustion rate / 24 * 22.4 - coal ratio * 8% / 32 * 22.4 = 439.4 * 0.67 / 24 * 22.4 - 145 * 8% * 22.4 / 32

[0085] =274.8-8.1=266.7m 3 / t

[0086] The third step is to calculate the comprehensive air volume entering the furnace

[0087] (a) Determine the hourly oxygen volume

[0088] It is known that the theoretical amount of iron in a day = 5700 tons.

[0089] Hourly oxygen volume = ton iron consumption oxygen volume * theoretical iron volume for the whole day / 24 = 266.7 * 5700 / 24

[0090] =63341m 3 / h

[0091] (b) Determine the air volume entering the furnace

[0092] According to the two equations "blast oxygen content + blast nitrogen content = 1" and "blast oxygen content = 0.21 + 0.29 * artificial humidity + 0.79 * oxygen usage rate", the air volume entering the furnace and the oxygen enrichment amount can be calculated.

[0093] Air volume into furnace = ((hourly blast oxygen volume - artificial humidification mass flow / 0.804 * (blast oxygen content - 0.21)) * (0.79 - (blast oxygen content - 0.21)) + (0.29 - (blast oxygen content - 0.21)) * hourly blast oxygen volume / 0.804) / (0.21 * (0.79 - (blast oxygen content - 0.21)) + (blast oxygen content - 0.21)) / 60

[0094] =((63341-0 / 0.804*(0.24-0.21))*(0.79-(0.24-0.21))+(0.29-(0.24- 0.21))*0 / 0.804) / (0.21*(0.79-(0.24-0.21))+(0.24-0.21)) / 60=4232m 3 / min

[0095] Among them, the artificial humidification mass flow rate, the quantity is zero;

[0096] Oxygen enrichment = hourly blast oxygen volume - furnace air volume * 60 * 0.21 - artificial humidification mass flow / 0.804 * 0.5

[0097] =63341-4232*60*0.21-0 / 0.804*0.5=10018m 3 / h.

[0098] (c) Determine the comprehensive air volume entering the furnace

[0099] Comprehensive air volume into the furnace = air volume into the furnace + oxygen enrichment / 60 + artificial humidification mass flow / 60 / 0.804

[0100] =4232+10018 / 60+0 / 60 / 0.804=4399m 3 / min.

[0101] Step 4: Calculate the kinetic energy of the wind

[0102] Known: Number of tuyere, 28; Blast weight, constant, 1.304kg / m 3 ; Air inlet area, 0.3065m 3 ; Hot air temperature, 1150℃; Hot air pressure, 335KPa; Standard atmospheric pressure, 100KPa; Absolute temperature, 273K;

[0103] Blast kinetic energy = 1 / 2*(comprehensive air volume into the furnace / number of air outlets / 60)*blast severity / 9.8*((comprehensive air volume into the furnace / 60 / air inlet area)*(hot air temperature+273) / 273*100 / (hot air pressure+100))^2

[0104] =1 / 2*(4399 / 28 / 60)*1.304 / 9.8*((4399 / 60 / 0.3065)*(1150+273) / 273*100 / (335+100))^2=14313kg.m / s. Example 2

[0105] The first step is to determine and calculate the carbon combustion rate

[0106] (a) Calculate the amount of gasified carbon. Given: K = 420 kg / t, M = 120 kg / t, C K =87%, C m =72%, C C =45kg / t. It can be seen that:

[0107] C g = K*C K + M*C m - C C =420*87%+120*72%-45=451.8-45=406.8kg / t

[0108] (b) Calculation of carbon combustion rate before tuyere

[0109] It is known that the oxygen content and nitrogen content of the blast air, O 2b =0.23, N 2b =0.77, O 2b + N 2b =0.23+0.77=1;

[0110] Composition of furnace top gas: CO2=23%, CO=22%, H2=2.5%, N2=52.5%; CO2+ CO+H2+N2=23%+22%+2.5%+52.5%=100%;

[0111] The amount of carbon burned before the tuyere = the amount of carbon burned by the oxygen in the blast + the amount of carbon consumed by the oxygen in the injected coal

[0112] C b = 2*N2 / (CO2+CO)*(O 2b / N 2b )*C g + M*O 2m / 32*24

[0113] =2*52.5% / (23%+22%)*0.23 / 0.77*406.8+(120*8%*24 / 32)

[0114] =290.7kg / t

[0115] C φ = C b / C f =290.7 / 451.8=0.64

[0116] The second step is to determine the oxygen consumption per ton of iron and the blast oxygen consumption per ton of iron

[0117] Blast oxygen consumption per ton of iron = 451.8*0.64 / 24*22.4-120*8%*24 / 32=269.9-7.2=262.76m 3 / t

[0118] The third step is to calculate the comprehensive air volume into the furnace

[0119] (a) Calculate the hourly oxygen volume of the blast

[0120] It is known that the theoretical amount of iron produced in a day is 7650 tons.

[0121] Hourly blast oxygen volume = 262.7*7650 / 24 = 83736m 3 / h

[0122] (b) Calculate the air volume entering the furnace

[0123] Air volume into furnace = ((83736-0 / 0.804*(0.23-0.21))*(0.79-(0.23-0.21))+(0.29-(0.23-0.21))*0 / 0.804) / (0.21*(0.79-(0.23-0.21))+(0.23-0.21)) / 60=5914m 3 / min

[0124] Oxygen enrichment = hourly blast oxygen volume - furnace air volume * 60 * 0.21 - artificial humidification mass flow / 0.804 * 0.5

[0125] =83736-5914*60*0.21-0 / 0.804*0.5=9220m 3 / h.

[0126] (c) Determine the comprehensive air volume entering the furnace

[0127] Comprehensive air volume into the furnace = air volume into the furnace + oxygen enrichment / 60 = 5914 + 9220 / 60 = 6068m 3 / min;

[0128] Step 4: Calculate the kinetic energy of the wind

[0129] Known: Number of tuyere, 32; Blast weight, constant, 1.304kg / m 3 ; Air inlet area, 0.40m 3 ; Hot air temperature, 1180℃; Hot air pressure, 410KPa;

[0130] Blast kinetic energy = 1 / 2*(comprehensive air volume into the furnace / number of air outlets / 60)*blast severity / 9.8*((comprehensive air volume into the furnace / 60 / air inlet area)*(hot air temperature+273) / 273*100 / (hot air pressure+100))^2

[0131] =1 / 2*(6068 / 28 / 60)*1.304 / 9.8*((6068 / 60 / 0.4065)*(1180+410) / 273*100 / (410+100))^2=19398kg.m / s. Example 3

[0132] The first step is to determine and calculate the carbon combustion rate

[0133] (a) Calculate the amount of gasified carbon. Given: K = 390 kg / t, M = 140 kg / t, C K =87%, C m =72%, C C =45kg / t; it can be seen that:

[0134] C g = K*C K + M*C m - C C =390*87%+140*72%-45=440.1-45=395.1kg / t

[0135] (b) Calculation of carbon combustion rate before tuyere

[0136] It is known that the oxygen content and nitrogen content of the blast air, O 2b =0.255, N 2b =0.745,O 2b + N 2b =0.255+0.745=1;

[0137] Determine the composition of the furnace top gas, CO2=21.5%, CO=26.5%, H2=2.5%, N2=49.5%, CO2+CO+H2+N2=21.5%+26.5%+2.5%+49.5%=100%

[0138] The amount of carbon burned before the tuyere = the amount of carbon burned by the blast oxygen + the amount of oxygen in the injected coal + the amount of carbon burned by itself

[0139] C b = 2*N2 / (CO2+CO)*O 2b / N 2b *C g + M*O 2m / 32*24

[0140] =2*49.5% / (21.5%+ 26.5%)*0.255 / 0.745*395.1+(140*8%*24 / 32)

[0141] =287.3kg / t

[0142] C φ = C b / C f =287.3 / 440.1=0.65

[0143] The second step is to determine the oxygen consumption per ton of iron and the blast oxygen consumption per ton of iron

[0144] Blast oxygen consumption per ton of iron = 440.1*0.65 / 24*22.4-140*8%*24 / 32=267.0-8.4=258.6m 3 / t

[0145] The third step is to calculate the comprehensive air volume into the furnace

[0146] (a) Calculate the total oxygen content of the hourly blast. Given that the theoretical amount of iron for the whole day is 6050 tons, we can know that

[0147] Total oxygen content per hour = 258.6*6050 / 24 = 65189m 3 / t

[0148] (b) Calculate the air volume entering the furnace.

[0149] Air volume into furnace = ((65189-0 / 0.804*(0.255-0.21))*(0.79-(0.255-0.21))+(0.29-(0.255-0.21))*0 / 0.804) / (0.21*(0.79-(0.255-0.21))+(0.255-0.21)) / 60=4018m 3 / min

[0150] Oxygen enrichment = hourly blast oxygen volume - furnace air volume * 60 * 0.21 - artificial humidification mass flow / 0.804 * 0.5

[0151] =65189-4018*60*0.21-0 / 0.804*0.5=14562m 3 / h;

[0152] (c) Calculate the comprehensive air volume entering the furnace

[0153] Comprehensive air volume into the furnace = air volume into the furnace + oxygen enrichment / 60 = 4018 + 14562 / 60 = 4261m 3 / min;

[0154] Step 4: Calculate the kinetic energy of the wind

[0155] Known: Number of tuyere, 28; Blast weight, constant, 1.304kg / m 3 ; Air inlet area, 0.30m 3 ; Hot air temperature, 1150℃; Hot air pressure, 340KPa;

[0156] Blast kinetic energy = 1 / 2*(comprehensive air volume into the furnace / number of air outlets / 60)*blast severity / 9.8*((comprehensive air volume into the furnace / 60 / air inlet area)*(hot air temperature+273) / 273*100 / (hot air pressure+100))^2

[0157] =1 / 2*(4261 / 28 / 60)*1.304 / 9.8*((4261 / 60 / 0.3065)*(1150+273) / 273*100 / (340+100))^2=12713kg.m / s. Example 4

[0158] The first step is to determine and calculate the carbon combustion rate

[0159] (a) Calculation of gasified carbon

[0160] Given: K = 400kg / t, M = 130kg / t, C K =87%, C m =72%, C C =45kg / t, we can know:

[0161] C g = K*C K + M*C m - C C =400*87%+130*72%-45=441.6-45=396.6kg / t

[0162] (b) Calculation of carbon combustion rate before tuyere

[0163] It is known that the oxygen content and nitrogen content of the blast air, O 2b =0.255, N 2b=0.745,O 2b + N 2b =0.255+0.745=1;

[0164] Composition of furnace top gas: CO2=24.0%, CO=23.0%, H2=2.5%, N2=50.5%, CO2+CO+H2+N2=24.0%+23.0%+2.5%+50.5%=100%

[0165] Carbon quantity burned before the tuyere = Carbon quantity burned by blast oxygen + Carbon quantity consumed by oxygen in injected coal

[0166] C b = 2*N2 / (CO2+CO)*O 2b / N 2b *C g + M*O 2m / 32*24

[0167] =2*50.5% / (24.0%+ 23.0%)*0.255 / 0.745*396.6+(130*8%*24 / 32)

[0168] =299.5kg / t

[0169] C φ = C b / C f =299.5 / 441.6=0.68

[0170] The second step is to determine the oxygen consumption per ton of iron and the blast oxygen consumption per ton of iron

[0171] Blast oxygen consumption per ton of iron = 441.6*0.68 / 24*22.4-130*8%*24 / 32=280.3-7.8=272.5m 3 / t

[0172] The third step is to calculate the comprehensive air volume into the furnace

[0173] (a) Calculate the hourly oxygen volume of the blast

[0174] It is known that the theoretical amount of iron produced in a day is 8,900 tons.

[0175] Hourly blast oxygen volume = 272.5*8900 / 24 ​​= 101052m 3 / t;

[0176] (b) Calculate the air volume entering the furnace.

[0177] Air volume into furnace = ((101052-0 / 0.804*(0.255-0.21))*(0.79-(0.255-0.21))+(0.29-(0.255-0.21))*0 / 0.804) / (0.21*(0.79-(0.255-0.21))+(0.255-0.21)) / 60=6228m 3 / min;

[0178] Oxygen enrichment = hourly blast oxygen volume - furnace air volume * 60 * 0.21 - artificial humidification mass flow / 0.804 * 0.5

[0179] =101052-6228*60*0.21-0 / 0.804*0.5=22579m 3 / h.

[0180] (c) Calculate the comprehensive air volume entering the furnace

[0181] Comprehensive air volume into the furnace = air volume into the furnace + oxygen enrichment / 60 = 6228 + 22578 / 60 = 6604m 3 / min;

[0182] Step 4: Calculate the kinetic energy of the wind

[0183] Known: Number of tuyere, 32; Blast weight, constant, 1.304kg / m 3 ; Air inlet area, 0.4065m 3 ; Hot air temperature, 1180℃; Hot air pressure, 410KPa;

[0184] Blast kinetic energy = 1 / 2*(comprehensive air volume into the furnace / number of air outlets / 60)*blast severity / 9.8*((comprehensive air volume into the furnace / 60 / air inlet area)*(hot air temperature+273) / 273*100 / (hot air pressure+100))^2

[0185] =1 / 2*(6604 / 32 / 60)*1.304 / 9.8*((6604 / 60 / 0.4065)*(1180+273) / 273*100 / (410+100))^2=18272kg.m / s.

Claims

1. A method for calculating the kinetic energy of blast furnace blast, Features: Follow these steps: Step 1: Determine and calculate the carbon combustion rate The calculation based on the carbon balance principle of blast furnace smelting law is as follows: (a) Calculation of gasified carbon According to C f =C g + C C =C b +C d +C c , C f =K*C K + M*C m , R = K + M, we know that C g = C f - C C = K*C K + M*C m - C C； in: C f , Carbon ratio refers to the amount of carbon entering the furnace, unit, kg / t; R, fuel ratio, unit, kg / t; K, coke ratio, unit, kg / t; M, coal ratio, unit, kg / t; C K , mass percentage of fixed carbon in coke, unit, %; C m , fixed carbon mass percentage of PCI coal, unit, %; C g , gasification carbon content, unit, kg / t; C b , refers to the amount of carbon burned before the tuyere, unit, kg / t; C C , carburized amount in pig iron, unit, kg / t; C d , Carbon consumption by direct reduction, unit, kg / t; (b) Calculation of carbon combustion rate before tuyere The amount of carbon burned before the tuyere = the amount of carbon burned by the oxygen in the blast + the amount of carbon consumed by the oxygen in the injected coal C b = C g / 12*22.4 / (CO+ CO 2 )*(N 2 / N 2b )*O 2b *24 / 22.4+M*O 2m / 32*24 = 2*C g *N 2 / (CO+ CO 2 )*(O 2b / N 2b )+ M*O 2m / 32*24 =2*N 2 / (CO+ CO 2 )*(O 2b / N 2b )*(C f -C C )+ M*O 2m / 32*24 =2*N 2 / (CO+ CO 2 )*(O 2b / N 2b )*(K*C K + M*C m -C C )+ M*O 2m / 32*24 C φ =C b / C f =2*N 2 / (CO+ CO 2 )*(O 2b / N 2b )*(K*C K +M*C m -C C ) / C f +(M*O 2m / 32*24) / C f =2*N 2 / (CO+ CO 2 )*(O 2b / N 2b )*(1-C C / C f )+(M*O 2m / 32*24) / C f in: C φ , carbon combustion rate before the tuyere, unit, %; O 2m , the mass percentage of oxygen in the injected coal, constant value, 8%; O 2b , volume percentage of blast oxygen, unit, %; N 2b , volume percentage of blast nitrogen, unit, %; CO, CO 2 , H 2 、N 2 , refers to the volume percentage of the top gas components, unit, %; CO+CO 2 +H 2 +N 2 =100%; Step 2: Determine oxygen consumption per ton of iron and blast oxygen consumption per ton of iron According to the known equation "oxygen consumption per ton of iron = oxygen consumption per ton of iron in blast air + oxygen consumption per ton of iron in injected coal", we can know that: Blast oxygen consumption per ton of iron = oxygen consumption per ton of iron - oxygen content in coal injected per ton of iron = carbon ratio * carbon combustion rate / 24 * 22.4 - coal ratio * 8% / 32 * 22.4; where: Oxygen consumption per ton of iron, oxygen consumption in blast air per ton of iron, oxygen content in coal injection per ton of iron, all in m 3 / t; Step 3: Calculate the comprehensive air volume entering the furnace (a) Hourly blast oxygen content Hourly oxygen volume = ton iron consumption oxygen volume * theoretical iron volume for the whole day / 24 Among them: theoretical iron content for the whole day, unit, t / d; oxygen content of the hourly blast, unit, m 3 / h; (b) Air volume into furnace According to the two known equations, "blast oxygen content + blast nitrogen content = 1" and "blast oxygen content = 0.21 + 0.29 * artificial humidity + 0.79 * oxygen rate"; where: 0.21, oxygen content in the atmosphere, constant; artificial humidity, the proportion of artificial humidification volume flow to the comprehensive air volume entering the furnace; oxygen rate, the proportion of oxygen-enriched volume to the comprehensive air volume entering the furnace; it can be known that: Air volume into furnace = ((hourly blast oxygen volume - artificial humidification mass flow rate / 0.804 * (blast oxygen content - 0.21)) * (0.79 - (blast oxygen content - 0.21)) + (0.29 - (blast oxygen content - 0.21)) * hourly blast oxygen volume / 0.804) / (0.21 * (0.79 - (blast oxygen content - 0.21)) + (blast oxygen content - 0.21)) / 60; Oxygen enrichment = hourly blast oxygen volume - furnace air volume * 60 * 0.21 - artificial humidification mass flow / 0.804 * 0.5; Where: 0.804, constant, density of water vapor under standard conditions, 18 / 22.4=0.804, unit kg / m 3 ; (c) Comprehensive air volume into the furnace Comprehensive air volume into the furnace = air volume into the furnace + oxygen enrichment / 60 + artificial humidification mass flow / 60 / 0.804; where: The air volume entering the furnace refers to the pure air volume entering the furnace, excluding the oxygen enrichment volume and artificial humidification mass flow rate, unit, m 3 / min; Comprehensive air volume into furnace, unit, m 3 / min; Oxygen enrichment, unit, m 3 / h; Artificial humidification mass flow rate, unit, kg / h; Step 4: Calculate the kinetic energy of the wind Blast kinetic energy = 1 / 2*(comprehensive air volume into the furnace / 60 / number of tuyere)*blast severity / 9.8*((comprehensive air volume into the furnace / 60 / air inlet area)*((hot air temperature+273) / 273)*(100 / (hot air pressure+100)))^2; Among them: kinetic energy of air blowing, unit, kg.m / s; number of air outlets, unit, piece; air inlet area, unit, m 2 ; Blast weight, constant, 1.304, unit, kg / m 3 ; Hot air temperature, unit, ℃; Hot air pressure, unit, KPa.

2. A method for calculating kinetic energy of blast furnace air according to claim 1, Features: The artificial humidification mass flow rate in the third step is zero when the blast furnace is in normal production and no artificial humidification is required; when the blast furnace is in abnormal condition, artificial humidification is required to restore the condition, unit, kg / h.