KR101808423B1 - Method for calculating sintering fuel input - Google Patents

Abstract

A method for calculating a sintered fuel input amount is disclosed. In one embodiment, the sintering fuel input amount calculation method includes the steps of: setting an expected sintering heat amount required in a sintering process of a raw material containing iron ore, an additive material, a sintered fuel, and water by the following formula 1; Calculating a first heat loss amount by evaporation of crystal water and evaporation of moisture in the compounding raw material during the sintering step; Calculating a first heat input amount, excluding a first heat loss amount, from the predicted sintering heat amount; And producing sintered ores by adding and sintering iron ores, additives, water and sintered fuel corresponding to the primary heat input to the sintering machine,
[Formula 1]
Estimated sintering heat (kcal) = estimated sintered fuel input (kg) x sintered fuel calorific value (kcal / kg)

Description

[0001] METHOD FOR CALCULATING SINTERING FUEL INPUT [0002]

The present invention relates to a method for calculating a sintered fuel input amount. More particularly, the present invention relates to a method for predicting the amount of sintering fuel to be quantitatively predicted, thereby calculating an optimal amount of sintered fuel to be contained in the raw material mixture.

The sintering process is a process for producing sintered ores by massing minute iron ores. This sintering process can be performed by a Dwight-Lloyd type sintering machine. The sintering process is performed by charging a blended raw material obtained by mixing an iron ore and an auxiliary raw material such as anthracite coal, coke, and limestone into a sintered bogie moving along an endless track. After the surface of the blended raw material charged in the sintered bogie is ignited and the atmosphere is sucked downward of the sintered bogie so as to pass through the ignited blended raw material, when the firebox moves to the bottom side of the sintered bogie, .

Since the Dwight-Lloyd sintering process uses the atmosphere in the open factory to supply the necessary oxygen for combustion, an atmosphere of about 1 million Nm ³ or more per hour is used. Therefore, the amount of heat lost during the sintering process varies with the atmospheric temperature.

BACKGROUND ART [0002] The background art of the present invention is disclosed in Korean Patent Laid-Open Publication No. 10-2002-0042952 (published on Jun. 6, 2002, entitled "Method for producing low oxidation sintered ores).

According to an embodiment of the present invention, there is provided a sintering fuel input amount calculation method capable of quantitatively predicting a heat amount lost by various process parameters during sintering operation.

According to an embodiment of the present invention, there is provided a sintered fuel injection amount calculation method capable of maintaining an optimum fuel injection amount required in sintering operation.

According to one embodiment of the present invention, there is provided a sintered fuel injection amount calculation method capable of producing an sintered ores having excellent drop strength.

According to an embodiment of the present invention, a sintering fuel input amount calculation method capable of efficient sintering operation and cost reduction and reduction of harmful gas generation amount is provided.

One aspect of the present invention relates to a method for estimating sintered fuel input amount. In one embodiment, the sintering fuel input amount calculation method includes the steps of: setting an expected sintering heat amount required in a sintering process of a raw material containing iron ore, an additive material, a sintered fuel, and water by the following formula 1; Calculating a first heat loss amount by evaporation of crystal water and evaporation of moisture in the compounding raw material during the sintering step; Calculating a first heat input amount, excluding a first heat loss amount, from the predicted sintering heat amount; And producing sintered ores by adding and sintering iron ores, additives, water and sintered fuel corresponding to the primary heat input to the sintering machine,

[Formula 1]

Estimated sintering heat (kcal) = estimated sintered fuel input (kg) x sintered fuel calorific value (kcal / kg)

In one embodiment, the primary loss heat quantity can be expressed by the following equation:

[Formula 2]

Primary heat loss (Kcal) = Heat loss by evaporation of crystal water in iron ore (kcal) + Heat loss by evaporation of moisture in sintered fuel (kcal)

In one embodiment, when the drop strength of the produced sintered ores is less than 92%, the sintered light absorption heat discharged from the sintering machine during the sintering process, the sintered light absorption heat remaining in the sintering machine, and the exhaust gas absorption heat discharged from the sintering machine Calculating the considered secondary heat loss; Calculating a second heat input amount by subtracting the second heat loss amount from the first heat input amount; And adding iron ore, additives, water, and sintered fuel corresponding to the secondary heat input to the sintering machine and sintering the sintered ores.

In one embodiment, the secondary loss heat quantity can be expressed by the following equation:

[Formula 3]

Secondary heat loss (Kcal) = Heat loss due to absorption heat of exhaust sintered heat (kcal) + Residual sintered light Heat loss due to absorption heat (kcal) + Heat loss due to exhaust gas absorption heat (kcal)

It is possible to quantitatively predict the amount of heat lost due to variables such as the actual temperature during the sintering process, the water content of the raw material mixture, and the absorption coefficient of the exhaust gas when the sintered fuel is calculated according to the sintering fuel input amount estimation method of the present invention. It is possible to predict quantitatively the optimum amount of fuel injection required, and to produce an sintered ore having excellent drop strength.

FIG. 1 shows a method of calculating the sintered fuel input amount according to one embodiment of the present invention.
2 is a photograph showing a comparison of the structure of the sintered ores according to the embodiment of the present invention and the comparative example of the present invention.

Hereinafter, the present invention will be described in detail. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to be exemplary, self-explanatory, allowing for equivalent explanations of the present invention.

Calculation method of sintered fuel input

One aspect of the present invention relates to a method for estimating sintered fuel input amount.

In the present specification, the sintering process is defined as a process of producing a sintered ores by injecting minute iron ores together with additives, water, and sintering fuel, and agglomerating them. In one embodiment, the sintering process may be performed by a Dwight-Lloyd sintering machine.

In one embodiment, the sintering process using the Dwight-Lloyd sintering machine is a process in which a sintering fuel is charged into a sintered bogie moving along an infinite orbit, and a sintering fuel is mixed with a raw material such as limestone and water, The surface of the sintered raw material charged into the sintered bogie can be ignited by using an igniter, and then the atmosphere can be sucked in the downward direction of the sintered bogie so as to pass through the ignited raw material. According to the inhalation of the atmospheric air, the sintering raw material fire extinguisher moves to the bottom of the sintering bogie so that sintering of the sintering raw material in the sintering bogie can be performed to produce sintered ores.

FIG. 1 shows a method of calculating the sintered fuel input amount according to one embodiment of the present invention. Referring to FIG. 1, the sintering fuel input amount calculating method includes: (S101) setting an expected sintering heat amount; (S102) calculating a primary loss heat amount; (S103) a first charged calorie calculation step; And (S104) a sintered-ore-producing step.

More specifically, the method for calculating the amount of sintered fuel includes the steps of: (S101) setting an expected sintering heat amount required in a sintering process of a raw material containing iron ore, an additive material, a sintered fuel and water; (S102) calculating a first heat loss amount due to evaporation of crystal water contained in the iron ore and evaporation of water in the raw material mixture during the sintering process; (S103) calculating a first heat input amount, excluding a first heat loss amount, from the predicted sintering heat amount; And (S104) adding iron ore, additives, water, and sintered fuel corresponding to the first heat input amount to a sintering machine and sintering the sintered ores.

Hereinafter, the sintering fuel input amount calculation method according to the present invention will be described step by step.

(S101) Estimated sintering heat quantity setting step

The above step is a step of setting an anticipated sintering heat amount required in a sintering process of a raw material mixture containing iron ore, additives, sintered fuel and water.

In one embodiment, the iron ore may be a minute iron ore having a particle diameter of 0.1 mm to 1 mm. In one embodiment, the additive can include one or more of limestone, silica sand and nickel-slag.

In one embodiment, the predicted sintering heat amount at the time of sintering of the blended material is calculated and calculated by the following formula 1:

[Formula 1]

Estimated sintering heat (kcal) = estimated sintered fuel input (kg) x sintered fuel calorific value (kcal / kg)

The sintered fuel may comprise at least one of anthracite coal and coke. In one embodiment, the calorific value of the anthracite is 6900 kcal / kg, and the calorific value of the coke is 7000 kcal / kg.

The sintered fuel estimated input amount can be set using sintered fuel cost data with respect to the total weight of the blended raw materials used in a usual sintering process. In one embodiment, the amount of the sintered fuel used may be in the range of 3.0 to 4.5 wt% based on the total weight of the raw material mixture.

(S102) Calculation of the first loss heat amount

The above step is a step of calculating a first heat loss amount due to evaporation of crystal water and evaporation of moisture in the blending raw material in the blending raw material during the sintering process.

In one embodiment, the primary loss heat quantity can be expressed by the following equation:

[Formula 2]

(Kcal) = heat loss (kcal) due to evaporation of crystal water in the raw material (kcal) + heat loss (kcal)

In the formula 2, the heat loss due to evaporation of crystal water and the heat loss due to moisture evaporation in the sintered fuel can be derived from the equations 2-1 and 2-2, respectively:

[Formula 2-1]

(Kcal) = (total heat absorption amount (kcal) by composition component of each ingredient of raw material x ratio of constituent components to ingredient raw material) by evaporation of crystalline water

[Formula 2-2]

(Kcal) = water content in the raw material (kg) x amount of heat absorbed by water (kcal / kg)

(In the formula 2-2, the heat absorbed by the moisture is 619 kcal / kg).

(S103) The first charged calorie calculation step

The above step is a step of calculating the first heat input amount excluding the first heat loss amount in the predicted sintering heat amount. Except for the above-mentioned primary heat loss amount, it is possible to quantitatively predict an optimal amount of fuel input during the sintering process, and the hardness and drop strength of the sintered ores can be excellent.

(S104)

In this step, the sintered fuel corresponding to iron ores, additives, water, and the heat of the first charge is added to a sintering machine and sintered to produce sintered ores.

If the amount of the first charged heat is less than the amount of heat required in the sintering process, the subsidiary material contained in the blended raw material does not melt or react, and the bonding strength of the sintered ores is lowered to lower the drop strength. When the amount of heat exceeding the amount of heat required in the process is exceeded, the fraction of the structure with low hardness is increased in the sintered ores, which may lower the drop strength of the sintered ores.

In one embodiment, when the drop strength of the produced sintered ores is 92% or more, the sintering process can be performed while maintaining the primary charged heat amount.

(S105) Calculation of the secondary loss heat amount

In this step, when the drop strength of the produced sintered ores is less than 92%, the sintered light absorption heat discharged from the sintering machine during the sintering operation, the residual sintered light absorption heat remaining in the sintering machine, and the exhaust gas absorption heat discharged from the sintering machine The calculated secondary heat loss is calculated.

1, when the drop strength of the sintered light is less than 92%, the sintered light absorption heat discharged from the sintering machine during the sintering process, the sintered light absorption heat remaining in the sintering machine, and the exhaust gas discharged from the sintering machine The sintering operation can be carried out by further considering the secondary heat loss considering the absorption heat.

For example, when the sintered light has a fall strength of less than 92% and a total amount of sintered ore of less than 17,300 ton / day, the sintering operation can be performed with further consideration of the secondary heat loss.

In one embodiment, the secondary loss heat quantity can be expressed by the following equation:

[Formula 3]

Secondary heat loss (Kcal) = Heat loss due to absorption heat of exhaust sintered heat (kcal) + Residual sintered light Heat loss due to absorption heat (kcal) + Heat loss due to exhaust gas absorption heat (kcal)

In the above formula 3, the heat loss due to the heat of exhaust sintered light absorption, the heat loss due to the residual sintered light absorption heat, and the heat loss due to the exhaust gas absorption heat can be derived by the following formulas 3-1, 3-2 and 3-3, respectively have:

[Formula 3-1]

(Kcal) = emission of sintering ore (kg) x emission sintering temperature (캜) x sintering specific heat (Kcal / kg / 캜)

[Formula 3-2]

Residual sintered light Heat loss due to absorption heat (kcal) = Residual sintered light (kg) x Residual sintered light temperature (° C) x Sintered specific heat (Kcal / kg /

[Formula 3-3]

(Kcal) = Sintering air flow rate (kg) x Specific heat of air (0.24 kcal / kg · ° C) x (Flue gas temperature (° C) - Air temperature (° C))

(S106) The secondary charged calorie calculation step

The step is a step of calculating the secondary heat input amount by subtracting the secondary heat loss amount from the primary input heat amount.

(S107) Step of producing sintered ores

In this step, sintered fuel corresponding to iron ores, additives, water, and the secondary heat input is charged into a sintering machine and sintered to produce sintered ores.

It is possible to quantitatively predict the amount of heat lost due to variables such as the temperature during actual sintering process, the water content of the blended raw material, and the exhaust gas absorption heat at the time of sintering fuel input calculated by the sintering fuel input amount calculating method of the present invention, It is possible to easily adjust the amount of heat input and maintain the optimum amount of fuel input required in the sintering operation and to produce sintered ores having a drop strength of 92% or more, , Cost reduction, and reduction in the amount of harmful gases such as CO ₂ , SOx, and NOx.

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

Examples and Comparative Examples

Example

The expected sintering heat amount required in the sintering process of the blended raw materials including minute iron ore, additives (limestone, silica sand and nickel-slag), sintered fuel (minute coke) and water was set by the following formula 1.

Estimated sintering calorie setting

The expected sintering heat amount required in the sintering process of the blended raw materials including minute iron ore, additives (limestone, silica sand and nickel-slag), sintered fuel (minute coke) and water was set by the following formula 1. The sintering process conditions are shown in Table 1 below.

[Formula 1]

Estimated sintering heat (kcal) = estimated sintered fuel input (kg) x sintered fuel calorific value (kcal / kg)

Sintering process conditions Ingredient Weight (kg) 63 Sintered fuel expected input (kg) 2.69 Calorific value of sintered fuel (Kcal / kg) 7,000 Water content (wt.%) 7.22 Heat absorption amount (kcal / kg) by moisture in the blended raw materials 619 Heat loss due to evaporation of crystal water (Kcal) 3037.6

Since the sintered fuel of 2.69 kg is used for 63 kg of the compounding raw material used in the normal sintering operation, the predicted sintering heat amount is set to 2.69 kg x 7,000 kcal / kg = 18,843 Kcal.

Calculation of primary loss heat

During the sintering process, the heat of crystallization in the blended raw materials as shown in Table 1 and the primary heat loss due to evaporation of water in the blended raw materials were calculated:

[Formula 2]

(Kcal) = heat loss (kcal) due to evaporation of crystal water in the raw material (kcal) + heat loss (kcal)

In the formula 2, the heat loss due to evaporation of crystal water and the heat loss due to moisture evaporation in the compounded fuel were calculated by the above-mentioned formulas 2-1 and 2-2, respectively.

(Kcal) = (total heat absorption amount (kcal) by composition component of each ingredient of raw material x ratio of constituent components to ingredient raw material) by evaporation of crystalline water

[Formula 2-2]

(Kcal) = water content in the raw material (kg) x amount of heat absorbed by water (kcal / kg)

The amount of the primary heat loss calculated according to the above Formulas 2, 2-1 and 2-2 was 3037.6 Kcal + ((63 kg x 0.0722) x 619 (kcal / kg)) = 5853.2 Kcal.

Calculation and sintering of primary input

The first heat input, excluding the first heat loss, was calculated as 12963.4 Kcal. Therefore, 1.85 kg of the sintered fuel corresponding to the above-mentioned first charged heat amount was added together with iron ore, a subsidiary raw material, a sintered fuel and water on the basis of the compounding raw material of 63 kg and sintered to produce an sintered ore. At this time, the atmospheric temperature at the time of sintering, the temperature of the exhaust gas discharged from the sintering machine, the specific heat of the sintered ores, the temperature of the sintered ores discharged from the sintering machine, the temperature of the sintered ores remained, .

Sintered ores (kg) discharged from the sintering machine 52.58 Sintering temperature (° C) discharged from sintering machine 218 Residual ore in sintering machine (kg) 5 Residual sintering temperature in sintering machine (℃) 470 Specific heat of sintering (Kcal / kg / ° C) 140 Air volume (kg) 59 Flue gas temperature (℃) 136.5 Ambient temperature (℃) 16.2

The drop strength of the produced sintered ores was measured to be about 90%.

Example  2

Calculation of secondary loss calories

As the drop strength of the sintered light produced in Example 1 was measured to be 90%, the emission heat of the sintered ores, the residual sintered-light absorption heat and the exhaust gas absorption heat discharged from the sintering machine were taken into account The secondary heat loss was calculated.

[Formula 3]

Secondary heat loss (Kcal) = Heat loss due to absorption heat of exhaust sintered heat (kcal) + Residual sintered light Heat loss due to absorption heat (kcal) + Heat loss due to exhaust gas absorption heat (kcal)

In Equation 3, the heat loss due to the heat of the exhaust sintered light absorption, the heat loss due to the residual sintered light absorption heat, and the heat loss due to the exhaust gas absorption heat are calculated by the following formulas 3-1, 3-2 and 3-3, respectively:

[Formula 3-1]

(Kcal) = emission of sintering ore (kg) x emission sintering temperature (캜) x sintering specific heat (Kcal / kg / 캜)

[Formula 3-2]

Residual sintered light Heat loss due to absorption heat (kcal) = Residual sintered light (kg) x Residual sintered light temperature (° C) x Sintered specific heat (Kcal / kg /

[Formula 3-3]

(Kcal) = Sintering air flow rate (kg) x Specific heat of air (0.24 kcal / kg · ° C) x (Flue gas temperature (° C) - Air temperature (° C))

The secondary heat loss amount calculated according to the above-described Formulas 3 and 3-1 to 3-3 is calculated as (52.58 Kcal x (218 占 폚 x 140 Kcal / kg / 占 폚) + (5 kg x (470 占 폚 x 140 Kcal / kg / DEG C)) + (59 x 0.24 x (136.5 DEG C - 16.2 DEG C)) = 3650.1 Kcal.

Calculation and sintering of secondary input calories

The amount of secondary heat input excluding the secondary heat loss was calculated as 9313.3 Kcal in the primary heat input. Thus, 1.33 kg of the sintered fuel corresponding to the secondary heat input amount was added together with iron ore, additives, sintered fuel and water on the basis of the compounding raw material of 63 kg, and sintered to produce sintered ores.

The drop strength of the produced sintered ores was about 94%, and the sintered ores (kg) discharged from the sinter was 53.4 kg. As a result, the drop intensity of the sintered ores was higher than that of Example 1.

FIG. 2 is a photograph showing a comparison of microstructures of the comparative sintered ore produced by Example 2 according to the present invention and 2.69 kg of sintered fuel according to the predicted sintering heat amount.

Referring to FIG. 2, in Example 2, the hardness was increased and the sintering intensity dropped to only 80% in Comparative Example. As shown in FIG. 2, , And the drop strength of the sintered ores decreased.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (4)

Setting an expected sintering heat amount required in a sintering process of a blended raw material including iron ore, a subsidiary raw material, a sintered fuel and water by the following formula 1;
Calculating a first heat loss amount by evaporation of crystal water and evaporation of moisture in the compounding raw material during the sintering step;
Calculating a first heat input amount, excluding a first heat loss amount, from the predicted sintering heat amount; And
And sintering the sintered fuel corresponding to the first input heat amount to produce a sintered ores;
When the drop strength of the produced sintered ores is less than 92%
Calculating a second loss heat amount considering the sintered light absorption heat discharged from the sintering machine, the sintered light absorption heat remaining in the sintering machine, and the exhaust gas absorption heat discharged from the sintering machine during the sintering process;
Calculating a second heat input amount by subtracting the second heat loss amount from the first heat input amount; And
The method of claim 1, further comprising the step of injecting and sintering iron ores, additives, water, and sintered fuel corresponding to the secondary heat input to the sintering machine to produce sintered ores.
[Formula 1]
Estimated sintering heat (kcal) = estimated sintered fuel input (kg) x sintered fuel calorific value (kcal / kg)
The method according to claim 1,
Wherein the first heat loss amount is expressed by the following formula (2): < EMI ID =
[Formula 2]
(Kcal) = heat loss (kcal) due to evaporation of crystal water in the raw material (kcal) + heat loss (kcal)
delete The method according to claim 1,
Wherein the secondary heat loss amount is expressed by the following formula (3): < EMI ID =
[Formula 3]
Secondary heat loss (Kcal) = Heat loss due to absorption heat of exhaust sintered heat (kcal) + Residual sintered light Heat loss due to absorption heat (kcal) + Heat loss due to exhaust gas absorption heat (kcal)

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