JP3205210B2 - Moisture control method for coal humidity control equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling moisture in humidified coal in a humidifying facility for coal charged in a coke oven.

[0002]

2. Description of the Related Art In a coke oven operation, the following three main advantages are obtained after the wet coal is dried and then charged into the coke oven.

[0003] The first point is that the heat exchange efficiency is higher than that of a coke oven (however, it cannot be performed until the carbonization of coal). The method of charging and carbonizing into a coke oven reduces the total energy consumption compared to the method of charging and directly carbonizing wet coal into a coke oven.

Second, by adjusting the moisture content of the wet coal, the variation in the moisture content of the coal charged into the coke oven is reduced, and the energy consumption in the coke oven is reduced.

[0005] Third, by drying the wet coal, the bulk density of the coal in the coke oven carbonization chamber is improved, the spacing between the coal particles is narrowed, and the coal particles in the carbonization process are promoted to improve the coke quality. (Drum strength, strength after CO ₂ reaction).

Next, the reason for drying the wet coal to the target moisture will be described below.

[0007] The lower the water content of the coal charged into the coke oven, the greater the above-mentioned energy consumption reduction effect and coke quality improvement effect.

On the other hand, as the water content of the coal is lower, operational obstacles such as dust generation during the transportation process and charging into the coke oven and carbon adhesion to the coke oven carbonization chamber and riser become more prominent. .

Therefore, it is necessary to operate with coal moisture at an appropriate point of the merits and demerits of the advantages and disadvantages, and the wet coal is dried to a certain target moisture.

[0010] In coal humidity control equipment, when performing the water control tone wet coal, in the JP-A-6-1085058, dryer outlet tone wet coal measured values of moisture (M _o) and the target dryer outlet A method is disclosed in which the amount of heat (Q) input to a dryer is adjusted based on the deviation (ΔM) of moisture conditioning coal moisture (M) to control moisture in conditioning moisture. FIG. 2 is a diagram showing this embodiment. In the figure, 1 is wet coal, 2 is a dryer inlet weigher, 3 is a dryer inlet moisture meter, 4 is a dryer, 5 is humidified coal, 6 is a dryer outlet moisture meter, and 7 is a dryer input calorie calculation unit. , 8 denotes a dryer input calorie adjuster operation amount calculator, and 9 denotes a dryer input calorie adjuster.

[0011]

However, in the above-mentioned method of adjusting the heat input to the dryer using the measured value of the moisture of the humidified coal at the outlet of the dryer, the steam generated from the humidified coal at the outlet of the dryer is not used. The moisture content of the humidified coal at the outlet of the dryer measured by the moisture meter 6 at the dryer outlet has an accuracy of ± 1% (absolute moisture) with respect to the true value. It was difficult.

According to the present invention, the humidity control is performed by using the actually calculated moisture at the outlet of the dryer, which is calculated from the material balance in the dryer, instead of the actually measured moisture at the outlet of the dryer, the measurement accuracy of which is extremely poor. The purpose is to accurately control the moisture of charcoal.

[0013]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides: (1) a method for controlling moisture in a coal humidity control equipment for drying wet coal charged into a coke oven to a target moisture with a dryer. Calculate the actual moisture content of the dryer at the outlet of the dryer, and calculate the moisture content of the dryer at the outlet of the dryer. A moisture control method for a coal humidity control facility, characterized in that the amount of heat input to the dryer is controlled based on the deviation between the coal moisture and the target moisture at the outlet of the dryer.

(2) In the method for controlling the moisture of the coal moisture conditioning equipment according to the above item (1), actual results are calculated from the measured input amount of the wet coal at the dryer inlet, the moisture of the wet coal at the dryer inlet, and the discharge amount of the wet coal at the dryer outlet. It is characterized in that the moisture at the outlet of the dryer is controlled by the following equation (1).

M _oc = 100 × {1−G _i / G ₀ × (1−M _i / 100)} (1) M _oc : actual calculation dryer moisture conditioning moisture [%] G _i : dryer Wet coal input [t / h] G ₀ : Dryer adjusted wet coal discharge [t / h] M _i : Dryer inlet wet coal moisture [%]

[0016]

According to the present invention, the moisture control of the humidified coal is performed by using the actual calculated humidified charcoal moisture at the dryer outlet instead of the actually measured value of the humidified coal moisture at the outlet of the dryer, calculated from the material balance in the dryer. Things.

FIG. 1 is a schematic diagram showing an example of an embodiment of the present invention.

The amount of wet coal 1 charged into the dryer 4 (G
_i ) and moisture (M _i ) are measured by the dryer inlet weigher 2 and the dryer inlet moisture meter 3. Further, the discharge amount (G ₀ ) of the humidified coal 5 discharged from the dryer is measured by the dryer outlet weigher 10.

Next, in the dryer outlet moisture conditioning moisture calculating section 11, the actual calculation dryer conditioning moisture moisture (M _oc ) is calculated by the equation (1) derived from the material balance of the coal and moisture passing through the dryer. ) Is calculated.

M _oc = 100 × {1−G _i / G ₀ × (1−M _i / 100)} (1) M _oc : actual calculation dryer moisture conditioning moisture [%] G _i : dryer Wet coal input [t / h] G ₀ : Dryer adjusted wet coal discharge [t / h] M _i : Dryer inlet wet coal moisture [%] Calculated actual result dryer dry outlet determined here Moisture is accurate to ± 0.3% (absolute moisture) relative to the true value. On the other hand, the actual measured value of the moisture of the conventional humidified coal at the dryer outlet has an accuracy of ± 1.0% (absolute moisture) with respect to the true value.

Further, in the dryer input calorie calculation unit 7,
The deviation (ΔM) between the moisture content (M ₀ ) at the outlet of the dryer and the moisture content (M) at the outlet of the target dryer and the dryer 4
(G _i ) and moisture (M _i )
The amount of heat (Q) to be put into the dryer is given by the following equation (2).
Calculate based on

Q _i = Q _i-1 + α · ΔM (2) ΔM = M _oc −M Q _i : Heat input to the current controlled periodic dryer Q _i-1 : Heat input to the previous controlled periodic dryer α: Constant M _oc : Actual calculation moisture of the moisture conditioning coal at the outlet of the dryer M: Moisture of the moisture conditioning moisture at the outlet of the target dryer In accordance with this calorie (Q), the operation quantity P of the dryer input heat quantity adjuster in the dryer input heat quantity controller operation quantity calculation unit 8 Is calculated, and further according to the manipulated variable P, the dryer input calorie adjuster 9
Is operated to control the temperature of the dryer 4 to control the moisture content of the humidified coal 5.

[0023]

[Example] In the actual control of the target drier outlet moisture conditioning charcoal moisture of 6.0%, the input amount of the damp coal at the dryer entrance and the discharge amount of the dampness conditioning coal at the dryer outlet were measured on a conveyor scale, and the moisture of the damp coal at the dryer entrance was measured by infrared rays. It was measured with a moisture meter, and from these measurement results (1)
Actual calculation of the accuracy of true value ± 0.3% (absolute moisture) calculated by the formula. Adjustment of the amount of heat input to the dryer based on the deviation between the moisture at the outlet of the dryer and the moisture at the outlet of the target dryer. Was carried out in a range of ± 4.5%, and as a result, the moisture-conditioning coal moisture at the dryer outlet could be controlled with an accuracy of 6.0 ± 0.5% (absolute moisture).
On the other hand, the control accuracy in this case in the conventional method is 6.0.
It was ± 1.5% (absolute moisture), and the control accuracy was greatly improved by the present invention.

[0024]

As described above, in the present invention, the actual calculated moisture content of the moisture at the outlet of the dryer, which is calculated from the material balance in the dryer, is used in place of the actually measured value of the moisture at the dryer outlet. By controlling the moisture of the humidified coal,
The target value can be controlled with high accuracy of ± 0.5% (absolute value).

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an example of an apparatus for explaining an embodiment of the present invention.

FIG. 2 is a configuration diagram of an apparatus for explaining a conventional technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Wet coal 2 ... Dryer inlet weighing device 3 ... Dryer inlet moisture meter 4 ... Dryer 5 ... Conditioning coal 6 ... Dryer outlet moisture meter 7 ... Dryer input calorie calculator 8 ... Dryer input calorie adjuster operation amount calculating unit 9 ... dryer heat input adjuster 10 ... dryer outlet weighers 11 ... dryer outlet temper coal moisture calculating unit G _i ... dryer wet coal charging amount [t / h] G ₀ ... drier tone Wet coal discharge [t / h] M _i : Moisture of wet coal [%] at the inlet of the dryer M ₀ : Moisture of moisture at the outlet of the dryer [%] M _oc : Moisture of the moisture at the outlet of the dryer [%] M ... target dryer outlet regulating wet coal moisture [%] .DELTA.M ... control moisture deviation [%] Q ... dryer heat quantity [W] Q _i ... current control cycle dryer heat quantity (W) Q _i-1 ... previous control cycle Heat input to dryer [W] P ... Operation amount of heat input to dryer [-] α ... Constant [-]

────────────────────────────────────────────────── (5) References JP-A-53-49366 (JP, A) JP-A-53-143602 (JP, A) JP-A-6-108058 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) C10B 57/10

Claims (2)

(57) [Claims] 1. A method for controlling moisture in a coal humidity control equipment for drying wet coal charged into a coke oven to a target moisture with a dryer, comprising: Calculate the moisture content of the humidified coal at the outlet of the dryer, and calculate the moisture content of the humidified coal at the outlet of the dryer. A moisture control method for a coal humidity control facility, comprising controlling a calorific value. 2. Calculation of the actual moisture content of the dryer at the outlet of the dryer from the measured input amount of the wet coal at the dryer inlet, the moisture content of the wet coal at the dryer inlet, and the discharge amount of the wet air at the dryer outlet. The method of controlling moisture in a coal humidity control facility according to claim 1, wherein M _oc = 100 × {1-G _i / G ₀ × (1-M _i / 100)} (1) M _oc : actual calculation drying machine outlet regulating wet coal moisture [%] G _i: dryer wet coal charging amount [t / h] G _0: dryer tone wet coal emissions [t / h] M _i: drier inlet wet coal moisture [%]