JPS59161479A - Method of cutting granules in dry cooler - Google Patents

Abstract

PURPOSE:Sensors are equipped so that the temperature of coke granules which are cut out at the outlet of the cooling tower and the number of coke cutting operations are detected to find the temperature difference from the cooling gas as well as the cutting speed to calculate the cutting interval, thus enabling the control of granule cutting so that the granules are uniformly cooled down. CONSTITUTION:A radiation type temperature sensor 17 is equipped so as to detect the temperature of the coke granules 15 which are cut through the valves 8a, 8b from the outlet 3a, 3b at the bottom of the cooling tower 1, further sensors 13 and 14 are installed to detect the number of granule cutting operations. The signals from these sensors are input into the arithmetic unit 18 and the amount of the granules is calculated in a certain time from the sensors 13, 14 to know the cutting speed and the temperature difference between the granules and the cooling gas is calculated from the signal of the sensor 17, then the interval of cutting valve operations is calculated so that the granules 15 become lower than the desired temperature to control the operations of the cutting valve 8.

Description

[Detailed description of the invention] The present invention relates to a cutting control method that enables cooling.

In the fields of steelmaking and chemical industry, there is a dry cooling method for the purpose of recovering the sensible heat of high-temperature granules. This is a method in which high-temperature agglomerates are put into a tower and all of the cooling gas is circulated to recover all the sensible heat of the agglomerates, which is then converted into steam energy at the boiler. Dry extinguishing equipment for red-hot coke is also a type of this method. However, the main idea will be explained below using all examples of coke dry fire extinguishing equipment.

As shown in Fig. 1, the coke dry extinguishing equipment has a cooling tower body 1, which has a red-hot coke inlet 2 at the top and an outlet 3 at the bottom to discharge all the cooled coke. . The upper part of the tower body 1 is connected to the upper part of the boiler 5 via a communication pipe 4, and the bottom of the boiler 5 and the lower part of the cooling tower body 1 are connected by a connecting pipe 7 with a fan 6 interposed therebetween. , a cooling gas such as an inert gas can be circulated by driving the entire fan 6. A cut-off valve 8 for cutting off coke in a patch manner is installed at the discharge port 3, and the operation of the cut-off valve 8 makes it possible to completely form a downward moving layer of coke within the column body 1. Therefore, the moving bed of coke flows countercurrently to the cooling gas, and the coke is cooled and the cooling gas is heated to a high temperature. This is K, please
A cooling gas that can cool coke and use the sensible heat of coke? Boiler 5vi can be heated through the heating system, resulting in energy saving effect? can be raised. 9 is an upper bunker, and 11 is a lower bunker on which an upper gate 10 is attached so that it can be opened and closed.

This dry cooling tower has the problem that cooling of the red-hot coke becomes uneven due to uneven flow of the cooling gas due to particle size segregation of the coke, unrestrained descent of grains, and the like. If the non-uniformity becomes noticeable, it is dangerous if high temperature coke is mixed in the coke cut out from the discharge port 3 by the cut-off valve 8 because it becomes dangerous.

For this reason, in the past, a plurality of temperature detection ends were placed on the circumferential wall of the cooling tower 1 to monitor the uneven cooling of coke during operation, and when a large difference occurred in the temperature distribution of the circumferential wall soil. In this case, the cut-out valve 8 was closed to stop the discharge of coke based on the approximation and correlation with non-uniform cooling.

However, it is not preferable to stop discharging coke. To address non-uniform cooling of coke without stopping coke discharge, cooling should be
It is conceivable to assume rL in advance and design the shape of the cooling tower body 1 commensurate with it.

However, in this case, you will have some extra space in your cooling capacity.
The shape of the column body 1 becomes large, which impairs economic efficiency as a facility for recovering sensible heat from coke. On the other hand, in order to deal with non-uniform cooling of coke, it is possible to consider a method of changing the supply amount of cooling gas in response to the non-uniform cooling. That is,
Is the cooling gas supply equipment all divided and supplied to areas with insufficient cooling? Increased amount of supply to the cooling excess section? The purpose is to uniformly cool the coke so that the amount of coke decreases. Furthermore, there is also a method of dividing the outlet of the cooling gas and appropriately restricting the total amount of gas discharged from each outlet to more uniformly cool the coke. There is also a method of increasing the total amount of cooling gas supplied in order to supply the non-uniform cooling section with the minimum amount of cooling gas required for cooling. According to the method of changing the supply amount of the cooling gas, the rising speed distribution of the cooling gas is as shown in FIG. Even if the speed is slow at the center 1c, by increasing the amount of gas supplied to the center 1c, the speed distribution can be made completely uniform, and coke cooling can be made completely uniform. However, each tower body is a moving bed of coke, and if the coke descending speed is high, there is a limit to how the total amount of cooling power supplied can be changed. In other words, as shown in FIG. 3, the descending velocity distribution of coke in the column body 1 has the slowest velocity at the center 1c, the fastest velocity between the center 1c and both wall surfaces ia and lb, and the maximum value. When the difference in the minimum value is large, if conventional methods are used to uniformly cool the entire coke, a large amount of cooling gas is forced to flow at full speed so that sufficient cooling gas is distributed even to areas where the falling speed is high. This required an increase in the size of the equipment, such as increasing the size of six fan bays, which was an inconvenience that would impair economic efficiency.

An object of the present invention is to provide a complete cutting control method for dry cooling equipment for grain agglomerates, which can uniformly cool grain agglomerates without completely stopping the discharge of grain agglomerates, and which can improve the economical efficiency of the equipment. It is.

In order to achieve the above object, the configuration of the present invention is to provide a radiation-type ♂1j temperature sensor that detects the temperature 1j ('l) of the agglomerates cut out from the outlet at the lower part of the cooling tower, and The multiple cutting valves installed in the grain agglomerate cutting device are used to detect the number of times the grain agglomerates are cut out.The temperature sensor and the number of cutting sensors are used to calculate the signals of the temperature sensor and the number of cutting times sensor. The total amount of agglomerates cut out within a certain period of time is calculated from the signal of the cutting number sensor to calculate the agglomerate cutting speed, and the agglomerate temperature from the temperature sensor signal is input into the cooling tower. Calculate the temperature difference between the previous cooling temperature or a preset reference temperature, calculate the optimum interval for the P operation from the temperature difference and the agglomerate cutting speed, and operate each cutting valve. In other words, the entire grain agglomerate is cooled to a uniform temperature.

A preferred embodiment of the present invention will be described below with reference to FIG.

As shown in FIG. 4, reference numeral 1 denotes a cooling tower body, and a discharge port 3 is provided at the bottom of the tower body for discharging cooled granules, that is, coke in this embodiment.

A plurality of discharge ports 3 are provided. Here, a case where two discharge ports 3 are provided will be described. A VC is provided so that coke can be discharged from each of the discharge ports 3a and 3b. Each outlet 3a, 3b [
Cut-out valves 8a and 8b are installed, and each outlet 3a is opened by the operation of each cut-out valve 8a and 3b.

VC is set to open and close 3b2. Each cut-out valve 8a.

8bvC is provided with cutting number sensors 13a and 13b for detecting the total number of cuttings of coke.

Also, 15 is coke discharged from the lower date 12,
16 is a belt conveyor that conveys this n-t. 1
Reference numeral 1 denotes a radiation type temperature sensor which measures the entire temperature of the coke 15 placed on the conveyor 16 and being moved. This one temperature sensor 17 and a plurality of cutting number sensors 13a, 13
b is electrically connected to the arithmetic unit 181C n1 temperature signal and cutting number signal? Input to the calculator 18. Arithmetic unit 18Vc
The coke cutting speed setting device 19 is connected to n1 operator 1.
Input all the coke cutting speed settings in 8. Arithmetic unit 18
The output side is connected to each cut-off valve 8a, 3blC, and controls the operation of each cut-off valve 8a, 8b by issuing an operation command signal 20.

To explain the functions of the calculator 18, first, the coke cutting speed is determined from the cutting number signal.

That is, the normal coke cutting speed V is calculated by the following equation.

Here, t is the elapsed time [time], Z is the number of times the coke is cut out within the elapsed time [times], and Q is the amount of coke cut out per time [tons/number of times].

On the other hand, the coke cutting speed V' during the transient period is calculated by the following equation.

Here, Vo is the coke cutting speed setting value [tons/hour]
, to and t', to-Q/vo [time 7 times], t'-, t/C [time 7 times], C is the integrated value of the number of coke cuttings within a certain elapsed time [times] . The period corresponding to the transient period is the start of coke cutting and the coke cutting speed setting value V. ? It refers to the period from when the change is made until a predetermined period of time has elapsed, and is the period until the change in coke cutting rate stabilizes at the minimum necessary level.

Second, the computing unit 18 continuously measures the temperature sensor 11.
The coke temperature θ1 of the cutoff valve 8a, the coke temperature θ4 of the cutoff valve 8b, and the cooling gas temperature θ before entering the column body 1.
. Temperature differences Δθi and Δθjt- are calculated, and average values H1 and i, ? are calculated for the temperature differences Δθi and Δθj. calculate. This calculation formula is shown as follows.

Here, N and M are the number of times the cutoff valves 8a and 8b are cut out within the set time.

Note that the temperature of the cooling gas before it flows into the tower body 1 is a value measured by a temperature sensor (not shown), but instead of this cooling gas temperature, it may be a reference temperature determined in advance based on the design.

Thirdly, the computing unit 18 calculates the temperature difference Δθ1. Based on Δθ, average temperature, etc., the interval Tl + of the average cutting time of valves 8a and 8b
Calculate 'r,,+TI'+T2'. That is, the interval T between the coke cutting times of the cutting valves 8a and 8b during normal times is calculated by the following equation.

On the other hand, the interval T' of the coke cutting time during the transient period is calculated by the following equation.

Next, the operation of the apparatus shown in FIG. 4 will be described.

The cutting speed setting value V is set in the cutting speed setting device 19. set,
The calculation unit 18 calculates the coke cutting time interval Tl p 'r21 T, / rT of each cutting valve 8a, 8b.
Adjust to z'. At this time, the cutting speed V1 r V2 r vIZ V2' at each cutting valve 8a, 8blC changes, and the descending speed of coke in the cooling tower body 1 changes.

When coke is unevenly cooled during normal operation, when the unevenly cooled coke is cut out, the temperature sensor 1
Temperature difference Δθi from temperature signal from γ.

Δθj and average value Δθ1. Calculator 1 sets ' to Δθj, Δθ
8, and it can be easily determined that the temperature was unevenly cooled. In addition, the cutoff valves 8 of the discharge ports 3a and 3b
Coke cutting speed v2 at the cutting valve 8a is calculated by the calculator 18 from the cutting number signals from the respective cutting number sensors 13a and 13b.

8b is also opened and closed by the computing unit 18, so the temperature difference Δ
It is also possible to easily determine which coke cutting speed corresponds to θi and ΔθjVc. Based on the calculated values of F and Takori et al., the optimum interval T+ of the cut-off time of each cut-off valve 8a, 8b is determined as shown in the above equation (5).
Calculated by the calculator 18 at T2, and the interval 'r,
The computing unit 18 outputs an operation command signal 20 such that each cutoff valve 8a, 8b operates at l'r2. Therefore, the joint venture
Temperature or Δθ1. If the average quality of Δθj is greater than its overall average value, then 10 of equation (5). /Kite or If)j/IO
Discharge port 3 where Q increases and high temperature coke is cut out and cooled
The operation interval Ti of cutting @8a and 8b corresponding to a and 3blC is increased. When the interval T becomes shorter, since the coke cutting amount Q is constant, the coke cutting speed V decreases (V=Q/T), and the coke descending speed becomes slower. As a result, the residence time in the furnace is extended, which improves the coke cooling effect and makes coke cooling more uniform. Conversely, the temperature difference Δθ1°Δθ is the average value Δ
If it is smaller than θ, the interglue Ti of the cutting time of the cutting valves 8a, 8b corresponding to the discharge ports 3a, 3b from which coke having a low temperature is cut out will be reduced, and the coke cutting speed V will increase. This increases the coke fall speed.

As a result, the residence time in the furnace is shortened, so the coke cooling effect is reduced and coke cooling is made more uniform.

Even when non-uniform cooling of coke occurs during a transient period, the temperature difference io, , 77? rj and its average value Δθ, and also the coke cutting speed v1'+ ”
2' is calculated by the calculator 18, and from these values the above (6) is calculated.
As shown in the formula, the interval TI'l Tz' k of the coke cutting time of each cutting valve 8a, 8b is calculated by the k calculator 18, and each cutting valve 5atab is operated at the interval TI'+T2'. The arithmetic unit 18 outputs an operation command signal 20. With this oven, the coke cutting speeds v1' and 2' of the respective cutoff valves 8a and 8b change, and the coke descending speed is changed, so the residence time in the oven is adjusted and coke cooling is made uniform. become.

By appropriately repeating the above operations, coke can be uniformly cooled both in normal and transient conditions.

Note that the radiation type temperature sensor 17 is not provided inside the cooling tower body 1 like a thermocouple, but one is provided outside the tower body 1.
The coke is cut out from each cutoff valve 8a, 8b and dropped from the lower gate 12 onto the belt conveyor 16, and the temperature of the coke is immediately detected as it is conveyed in batches on the conveyor 16.

In other words, when installing a thermocouple χ・J inside the cooling tower body 1, the thermocouple must be buried in the brick wall of the tower to prevent wear, so it is difficult to accurately measure the temperature of coke inside the tower body 1. Moreover, the coke inside the column body 1 is still in the process of being cooled, and cannot be called cooled coke. Moreover, inside the tower body 1, the thermocouple detects the temperature of the gas and the response is slow. However, the radiation temperature sensor 1
7 outside the column body 11 as shown in Figure 4, there is no disturbance and the true temperature of the coke after cooling can be measured.
Moreover, the installation environment is better than when installed inside the tower body 1.
A long life can be expected, maintenance is easy, and the response is quick, so changes in process values can be quickly detected and used to control the cutoff valves 8a and 8b.

In summary, the present invention exhibits all the following excellent effects.

(1) Agglomerates can be uniformly cooled without having to completely stop discharging the agglomerates, improving the operating rate of the dry cooling system, and using multiple cut-off valves, each cut-out valve can be opened and closed. By controlling the interval, the rate of descent of the agglomerates in the cooling tower can be controlled, and cooling of the agglomerates can be reliably uniformed.

(2) It is also possible to control the cutoff valve during normal and transient times. In particular, since the temperature of the agglomerates cut out from the outlet at the bottom of the cooling tower is detected by a radiation-type temperature sensor, there is no disturbance compared to when thermocouples are installed inside the cooling tower, and the temperature of the coke after cooling is reduced. It can detect the true temperature, has a fast response, and uniformly cools the agglomerates with high precision.Moreover, it has a good installation environment, can be expected to have a long life, and is easy to maintain.

(3) According to the method of installing a thermocouple in the furnace to determine the temperature of the agglomerates, at least several thermocouples are required for the cut-out valve, but due to the capacity of the subsequent equipment, the cut-out valve can be installed once. Since multiple cut-off valves do not open or close at the same time, by linking with the cut-off frequency sensor, even if there are multiple cut-off valves, one radiation-type temperature measurement sensor can control the cut-off time for each cut-off valve. It is possible to detect the temperature of the ejected pellets.

[Brief explanation of the drawing]

Figure 1 is a longitudinal sectional elevation view showing an example of a conventional dry fire extinguishing system for pellets, Figure 2 is an explanatory diagram showing the distribution of the cooling gas rising speed ratio in the cooling tower body of Figure 1, and Figure 3 is What is the distribution of the falling speed ratio of the particles in the cooling tower body in Figure 1? The explanatory diagram shown,
FIG. 4 is a front view of an M new machine showing an example of an apparatus for carrying out the present invention. In addition, in the figure, 1 is a cooling tower, 3a, 3b are discharge ports, 8a, gb
13 and 14 are cutting valves, 13 and 14 are cutting number sensors, 15 is coke, 11 is a temperature sensor, and 18 is a computing unit. Patent applicant: Ishikawajima-Harima Heavy Industries Co., Ltd. Agent: Patent attorney: Nobuo Kinutani Figure 1 Figure 2 Figure 3/

Claims (1)

[Claims] A radiation-type temperature sensor is provided to detect the temperature of the agglomerates cut out from the outlet at the bottom of the cooling tower, and the agglomerates are fed to a plurality of cutting valves provided in the agglomerate cutting device at the bottom of the cooling tower. Is there a full cutting number sensor that detects the total number of times the lump is cut out, and a signal from the temperature sensor and cutting number sensor? The input is input to a calculator, and the total amount of agglomerates cut out within a certain period of time is calculated from the signal of the cutting number sensor, the agglomerate cutting speed is calculated, and the agglomerate temperature from the signal of the temperature sensor and the amount in the cooling tower are Calculate the temperature difference between the cooling gas temperature before entering or a preset reference temperature, and calculate the cut-out valve operation interval from the temperature difference and the agglomerate cutting speed so that the agglomerate temperature is below the desired temperature. Th%
A method for controlling the cutting of agglomerates in dry cooling equipment based on the characteristics.