RU2096497C1 - Method of producing fluxed agglomerate - Google Patents

Abstract

FIELD: lime agglomerate production. SUBSTANCE: invention aims at developing process with differentiated distribution of lime in process lines when producing fluxed agglomerate. To this aim, one preliminarily determines dependence of productivity of caking process on lime intake into charge, which intake is chosen from zero to its optimum value. Then one calculates difference in productivities for two close lime intake values and therefrom finds critical lime intake corresponding to maximum specific productivity change and calculates largest number of lines which are provided by critical lime intake (A) according to formula : F = q_E/q_cr-δ where q_E is summary intake of lime for agglomerate production; g_cr critical intake of lime per one line; and δ fractional residue of division of q_E by g_cr. If A is less than available number of lines, results of determining dependence of productivity of caking process on lime intake, one calculates, using interpolation technique, change in productivities Δ₁ and Δ₂ from formulas: Δ₁=Q₁-Q₀ and Δ₂=A(Q₁- Q_cr) where Δ₁ and Δ₂ are changes in productivity of one line when increasing lime intake from zero to q_E-q_crA and change in productivity of A lines when increasing lime intake from g_cr to q_cr+(q_E-q_cr•A)/A+, respectively; and Q_o, Q₁, Q₂, and Q_cr are productivities of one line at zero lime intake, q_ε-q_crA, q_cr+(q_E-q_crA)/A, and g_cr, respectively. In addition, if Δ₁> Δ₂, A lines are involved to doze into charge g_cr of lime each or one line to doze g_E-g_crA of lime. If Δ₁ < Δ₂, A lines are involved to doze into charge q_E/A of lime each. EFFECT: optimized process parameters. 2 tbl

Description

 The invention relates to the field of preparation of raw materials for metallurgical processing and can be used for the production of fluxed iron ore sinter.

 A known method for the production of fluxed agglomerate, which consists in dividing the process into two separate production lines, each of which will include dosing of concentrate, sinter ore, fuel and limestone, mixing, pelletizing and sintering of the charge [1] The disadvantage of this method is the low productivity of the sintering process due to poor crumple charge insufficient strength of pelletized pellets.

 A known method for the production of fluxed agglomerate by dividing the process into two separate production lines, including dosing of concentrate, sinter ore, fuel, limestone and lime, mixing, pelletizing and sintering of the charge. The average consumption of lime in the mixture is below optimal, while lime is evenly distributed between both streams [2] The method allows to increase the productivity of the process due to the use of an intensifying lime additive in the mixture.

 The known method does not provide high productivity of the sintering process due to the irrational uniform distribution of lime over both streams. In conditions of insufficient lime to ensure its optimal flow rate into the charge of each stream, uniform dosing of lime over the streams does not allow the best use of the intensifying properties of all the lime spent on the production of sinter. This is due to the fact that the intensifying effect of lime on the sintering process is not directly proportional to the dependence on the consumption of this additive in the sinter charge. A change in the flow rate of lime into the charge by the same amount has a different effect on the productivity of the process and depends on the absolute value of the flow rate of the intensifying additive. The known method does not take into account this circumstance, the specific features of which are determined by the composition and properties of the mixture, as well as the quality of the lime used.

 The aim of the invention is to increase the productivity of the sintering process by increasing the efficiency of use of lime.

где
A наибольшее число линий, которые обеспечиваются критическим расходом извести;
q_Σ - суммарное потребление извести на производство агломерата;
q_кр потребление извести по одной линии при критическом расходе извести;
d - дробный остаток при делении q_Σ на q_кр, если A меньше числа линий, то, по результатам определения зависимости производительности от расхода извести, вычисляют интерполированием изменение производительностей D₁ и Δ₂ по формулам Δ₁=Q₁-Q_o и Δ₂=A(Q₂- Q_кр), где Δ₁ и Δ₂ изменение производительностей одной линии при увеличении потребления извести от 0 по (q_Σ-q_кр•A) и A линий при увеличении потребления извести от q_кр по

; Q₁, Q₀, Q₂ и Q_кр производительности одной линии при потреблениях извести, равных

и q_кр, при этом, если Δ₁ > Δ₂ то дозируют в шихту A линий по q_кр извести, а в шихту одной линии (q_Σ-q_кр•A) извести если Δ₁ < Δ₂ то дозируют в шихту A линий по

извести.This goal is achieved by the fact that in the known method for the production of fluxed sinter, which consists in dividing the process into separate production lines, dosing iron ore material, fuel, limestone and lime, with an average consumption of lime below the optimum, mixing, pelletizing and sintering of the charge, the process productivity is preliminarily determined sintering at a flow rate of lime in the mixture in the range from zero to optimal, calculate the difference in productivity at adjacent costs of lime and ahodyat its critical flow rate corresponding to the maximum specific performance changes, expect the greatest number of lines that provided the critical flow of lime according to the formula:

Where
A the largest number of lines that are provided with a critical flow of lime;
q _Σ - total lime consumption for sinter production;
q _cr consumption of lime in one line at a critical consumption of lime;
d is the fractional residue when dividing q _Σ by q _cr , if A is less than the number of lines, then, according to the results of determining the dependence of productivity on lime consumption, calculate the change in productivity D ₁ and Δ ₂ by the formulas Δ ₁ = Q ₁ -Q _o and Δ ₂ = A (Q ₂ - Q _cr ), where Δ ₁ and Δ ₂ change the productivity of one line with an increase in lime consumption from 0 by (q _Σ -q _cr • A) and A lines with an increase in lime consumption from q _cr

; Q ₁ , Q ₀ , Q ₂ and Q _{cr the} productivity of one line with lime consumption equal to

and q _cr , _moreover , if Δ ₁ > Δ _2, then lime is dosed into the charge A of lines q _qr , and lime is dosed into a single charge (q _Σ -q _cr • A); if Δ ₁ <Δ _2, then dosed into charge A lines along

lime.

устанавливают один из следующих вариантов распределения извести по линиям: 1) в A линий шихты подают по q_кр потребления извести, а в одну линию остаток потребления извести (частным случаем этого варианта является подача всей извести в одну линию, когда A 0); 2) в A линий шихты подают по

потребления извести. Предложенный способ производства офлюсованного агломерата обеспечивает такое распределение извести между технологическими линиями, при котором в максимальной степени используются интенсифицирующие свойства извести для данных условий производства. Это приводит к увеличению производительности агломашины при одновременном повышении качества агломерата, поскольку оптимизация процесса спекания способствует улучшению структуры спека.The essence of the claimed solution is characterized by the presence of a combination of actions, including one distinguishing feature of the differentiated distribution of lime along production lines. To determine the variant of differentiated distribution of lime in relation to specific production conditions, a certain set of preliminary actions is proposed, including: 1) physical modeling of the method of sinter production with simultaneous control of the main technology parameters; 2) calculations and analysis of the results. Depending on the indicated ratios between changes in productivity

one of the following options for distributing lime along the lines is established: 1) q _{cr of} lime consumption is fed to A lines of the charge, and the remainder of lime consumption is fed to one line (a special case of this option is to supply all the lime in one line when A 0); 2) in A lines of the charge serves on

lime consumption. The proposed method for the production of fluxed agglomerate provides such a distribution of lime between production lines, in which the intensifying properties of lime for these production conditions are used to the maximum extent. This leads to an increase in the performance of the sinter machine while improving the quality of the sinter, since the optimization of the sintering process improves the structure of the sinter.

на каждую из них. В связи с дифференцированным дозированием извести по линиям, для получения одинаковой основности агломерата устанавливают расход известняка в шихту каждой линии обратно пропорционально расходу извести. Шихту смешивают, окомковывают по каждой технологической линии отдельно.The method of fluxed agglomerate by dividing the process into separate production lines is as follows. In the batch department of the sinter plant, iron ore material, fuel, and limestone are dosed on each line. To establish the flow rate of lime on separate lines experimentally (laboratory or industrial), the process productivity is determined at several flow rates of lime per charge, which are in the range from zero to optimal, the critical flow rate of lime is found and the maximum number of lines is calculated, into the charge of which a critical flow rate of lime can be supplied . If it turns out that A is less than the number of lines (for the case when A is equal to or more than the number of lines), (for the case when A is equal to or more than the number of lines, in accordance with the theoretical concept of the proposed technical solution, the dosage of lime should be uniform over all flows , however, this option is not mentioned in the claims, because it is contained in the prototype), then Δ ₁ and Δ ₂ are calculated. When Δ _{1 is} greater than Δ _{2, the} critical flow of lime is dosed along A lines, and the remainder of the lime (q _Σ -q _cr • A) serves in one of the remaining lines. When Δ ₁ less than Δ ₂ lime is dosed only on A lines in the amount

on each of them. In connection with the differentiated dosage of lime along the lines, in order to obtain the same basicity of the agglomerate, the limestone flow rate in the charge of each line is inversely proportional to the lime flow rate. The mixture is mixed, pelletized for each production line separately.

Из табл. 1 имеем удельную производительность при нулевом и критическом расходе извести в шихту, кг/м²сек: Q $\genfrac{}{}{0ex}{}{\text{′}}{\text{o}}$ = 0,278; Q $\genfrac{}{}{0ex}{}{\text{′}}{\text{1,371}}$ = 0,417. Интерполированием определяем удельную производительность при потреблении извести, равном 0,887 и 1,667 кг/сек:

Вычисляем удельные изменения производительности:

(замена общих изменений производительностей, упоминаемых в формуле изобретения

и

, где S₁ площадь спекания по одной линии, на соответствующие удельные

не отражается на соотношениях между ними).The production of fluxed agglomerate with a basicity of 1.2 was carried out by dividing the process into several independent technological lines in relation to the conditions of the sinter plant of NKGOK. The mixture consisted of magnetite concentrate, sinter ore, coke breeze, limestone and lime. The average consumption of lime in the mixture over all lines was below the optimum, equal to 60 kg / t. Each production line included dosing of the charge components, mixing, pelletizing, sintering of the charge on an sinter machine with an area of 75 m ² . The performance of the sintering process at several costs of lime to the mixture, ranging from optimal to zero, was determined in laboratory conditions, which corresponded to the industrial composition of the mixture, the modes of its preparation and sintering. The critical lime consumption was determined in the most rational way, ensuring the minimum number of points in the studied interval of lime consumption: dividing the initial interval into two equal segments, finding a segment having a large value of the specific productivity change, dividing the found interval into two equal segments, etc. until the same value of the specific change in productivity on two adjacent segments. The highest consumption of lime in the mixture, providing the maximum specific change in productivity, will be the initial critical consumption of lime. The results of laboratory sintering and determination of the critical consumption of lime by them are presented in table. 1, from which it follows that the critical consumption of lime is 37.50 kg / t. This consumption corresponds to a specific productivity of the installation, equal to 0.417 kg / m ² sec, and consumption of lime along one line, equal to 1.371 kg / sec. In the table. Figure 2 presents several options for the initial conditions for the production of sinter (number of lines from 2 to 4, total consumption of lime from 1.25 to 5.00 kg / s) and indicators of sinter production in various ways (differentiated and uniform dosing of lime along the lines). As an example, consider the sequence of determining the parameters of the differential dosage of lime along the lines with the number of lines equal to 4, and the total consumption of lime 5.00 kg / s. We find the largest number of lines into the charge of which you can apply the practical consumption of lime: A 5.00 / 1.371 0.65 3. Since A is less than the number of lines, according to the data in Table 1, we calculate the productivity change with an increase in the flow of lime to the mixture from 0 by (q _Σ -q _cr • A) 5.00-1.371 • 3 = 0.887 kg / s and from

From the table. 1 we have the specific productivity at zero and critical consumption of lime in the mixture, kg / m ² sec: Q $\genfrac{}{}{0ex}{}{\text{′}}{\text{o}}$ = 0.278; Q $\genfrac{}{}{0ex}{}{\text{′}}{\text{1,371}}$ = 0.417. By interpolating, we determine the specific productivity for the consumption of lime equal to 0.887 and 1.667 kg / s:

We calculate the specific changes in productivity:

(replacement of general productivity changes referred to in the claims

and

where S ₁ the sintering area in one line, to the corresponding specific

does not affect the relationships between them).

(0,074<0,096), то в шихту трех линий дозируем по 5,00 3 1,667 кг извести/сек, а в оставшуюся линию известь не подаем совсем (вариант 12). При этом имеем суммарную производительность процесса 122,229 кг/сек против 120,048 кг/с по известному способу. Попытка применения другого варианта дифференцированного дозирования извести при этих же исходных условиях производства (вариант 13) дозирование в шихту трех линий критического расхода извести (q₁= q₂=q₃=1,371 кг/с), а в шихту четвертой линии остатка извести (q₄ 5-3•1,371 0,887 кг/с) - приводит не только к снижению суммарной производительности процесса по сравнению с предлагаемым способом, но дает худшие результаты по сравнению с известным способом (при равномерном дозировании извести по всем линиям).Because

(0,074 <0,096), then we dose 5.00 3 1,667 kg of lime / s into the mixture of three lines, and we do not give lime to the remaining line at all (option 12). Moreover, we have a total process productivity of 122.229 kg / s versus 120.048 kg / s according to the known method. An attempt to use another variant of differentiated dosing of lime under the same initial conditions of production (option 13) dosing into the charge of three lines of critical lime consumption (q ₁ = q ₂ = q ₃ = 1.371 kg / s), and into the mixture of the fourth line of lime residue (q ₄ 5-3 • 1.371 0.887 kg / s) - not only leads to a decrease in the total productivity of the process compared to the proposed method, but gives worse results compared to the known method (with uniform dosing of lime along all lines).

 From the table. 2 shows that the proposed method for the production of fluxed agglomerate allows to increase the productivity of the sintering process by 5-10% by increasing the efficiency of lime use. The strength of the agglomerate also increases (the fines content of the 5-0 mm fraction in the agglomerate decreases by an average of 0.7 1.3% rel.). This result is a consequence of the differentiated dosage of lime along separate production lines, which ensures the maximum use of the intensifying properties of lime for specific conditions for the production of sinter at a total consumption of lime below the optimum.

Sources of information
1. N.M. Bondarenko, M.G. Zaitseva, G.N. Zimokos and others. The southern enrichment plant will pick up pace. Dnepropetrovsk: Promin, 1966, p.21.

 2. A.G. Astakhov, A.I. Machkovsky, A.I. Nikitin, N.V. Fedorovsky. Handbook of agglomeration. Kiev: Technics, 1964, p. 185, 188-189.

Claims (1)

A method for the production of fluxed sinter, including dividing the process into separate production lines, dosing iron ore material, fuel, limestone and lime, the average consumption of which is below optimal, mixing, pelletizing and sintering of the charge, characterized in that the dependence of the productivity of the sintering process on the consumption of lime in the charge, which is taken in the range from zero to optimal, calculate the difference in productivity at adjacent costs of lime and find its cr matic flow rate corresponding to the maximum change in the specific performance, then calculated the largest number of lines, which are provided critical flow lime, according to the formula

where A is the largest number of lines that are provided with a critical consumption of lime;
q _Σ is the total consumption of lime for the production of sinter;
q _{k p} critical lime consumption in one line;
d is the fractional remainder when dividing q _Σ by q _cr ,
if A is less than the number of lines, then according to the results of determining the dependence of productivity on lime consumption, the change in productivity Δ ₁ and Δ _{2 is} calculated by interpolation using the formulas
Δ ₁ = Q ₁ - Q ₀ ;
Δ ₂ = A (Q ₂ - Q _cr ),
where Δ ₁ is the change in the productivity of one line with increasing consumption of lime from zero to (q _Σ - q _cr • A);
Δ ₂ - a change in the productivity of A lines with an increase in lime consumption from q _{to p} to

Q _{0 the} productivity of one line at a flow rate of lime equal to zero;
Q _{1 the} productivity of one line at a flow rate of lime equal to q _Σ - q _cr • A;
Q _{2 the} productivity of one line at a flow rate of lime equal to

Q _{to p the} productivity of one line at a flow rate of lime equal to critical,
wherein if Δ _1> Δ _2, in the charge A lines dosed by q _{to p} lime, and the charge of one line - (q _Σ - q _cr • A) lime, and if Δ ₁ <Δ _2, then metered into the batch And the lines on

lime.

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