JP2005015530A - Method for supplying water to boiler of coke dry quenching installation and facility for supplying water - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for supplying water to a boiler of a coke dry quenching installation, by which cooling temperature to a cooling tower can be lowered with a low cost installation without causing dew condensation corrosion, and to provide a facility for supplying water. <P>SOLUTION: The method for supplying water to the boiler of the coke dry quenching installation, comprising charging red-hot coke into a cooling tower 1, blowing an inert gas into the cooling tower 1 to exchange the heat, delivering the heat-exchanged inert gas into the boiler 4, exchanging the heat of the delivered inert gas with the heat of cooling water supplied from the water supply tank 12 to the boiler 4 to recover the waste heat, and then returning and recycling the recovered inert gas to the cooling tower 1, is characterized by supplying the cooling water from the water supply tank 12 to a deaerator 16 to subject the cooling water delivered from the deaerator 16 and the cooling water supplied from the water supply tank 12 to the deaerator 16 to a heat exchange, and then supplying the heat-exchanged cooling water delivered from the deaerator 16 to the boiler 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water supply method and a water supply device for cooling water supplied to a boiler for recovering heat from exhaust gas generated when coke in a coke dry fire extinguishing system is cooled.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, there is a heat recovery device for a coke dry fire extinguishing facility as shown in FIG. As shown in the figure, the cooling tower 1 constituting the main part of the coke dry fire extinguishing equipment is provided with a coke charging port for charging red hot coke at the upper part thereof, and the cooled coke is provided at the lower part of the cooling tower 1. A coke discharging device is provided for removing the coke. In the upper part of the cooling tower 1, there is provided a circulation duct 2 for sending high-temperature exhaust gas exchanged with sensible heat of red hot coke to the boiler 4, and dust contained in the high-temperature exhaust gas is placed in the middle of the circulation duct 2. A primary dust catcher 3 for collecting is provided.
[0003]
The boiler 4 is provided with a heat exchanger 5 connected to the water supply pipe 24. The heat exchanger 5 includes a superheater 6, an evaporator 7, and a economizer 8. Heat exchange is performed between the cooling water flowing in the heat exchanger 5 and the exhaust gas supplied into the boiler 4. . A circulation duct 9 for discharging low-temperature gas after heat exchange is connected to the lower part of the boiler 4. The circulation duct 9 is connected to the cooling tower 1 and the exhaust gas is circulated. In the circulation duct 9 through which the low temperature exhaust gas passes, a dust collector 10 for collecting dust and a circulation blower 11 for sending the low temperature exhaust gas to the cooling tower 1 are arranged. A feed water preheater 23 is disposed between the circulation blower 11 and the cooling tower 1.
[0004]
The cooling water sent from the water supply tank 12 by the degassing water supply pump 13 is sent to the water supply preheater 23 via the supply pipe 21 and is heat-exchanged with the exhaust gas flowing through the circulation duct 9 to bring the exhaust gas temperature to a predetermined temperature. Cooling. On the other hand, since the cooling water sent from the feed water preheater 23 through the drain pipe 22 is heat-exchanged with the exhaust gas and the temperature rises, the feed water heat exchanger 20 is disposed on the outlet side of the feed water preheater 23. Then, heat is exchanged with the cooling water sent from the water supply tank 12 and sent to the deaerator 16. The degassed cooling water is supplied to the boiler 4 by the boiler feed pump 18. 2 denotes an air / water cylinder.
[0005]
Further, in Patent Document 1, a first heat exchanger is provided in a circulation duct connecting a boiler and a cooling tower, a second heat exchanger is provided in a boiler feed water line, and a heat medium is provided between both heat exchangers. A heat recovery device is disclosed that forms an enclosed closed circulation path. Specifically, the circulating gas that extinguishes the red hot coke in the cooling tower is sent to the boiler through the dust catcher. And boiler feed water and heat exchange are performed and it cools to about 180 degreeC. The circulating gas after the heat exchange is sent to the first heat exchanger by a blower, where the circulating gas that has given heat to the heat medium is cooled to about 130 ° C. and introduced into a cooling tower to cool the red hot coke. On the other hand, the boiler feed water cooling water stored in the feed water tank is heated to about 65 ° by the second heat exchanger by the pump, sent to the deaerator and deaerated. Thereafter, water is supplied to the boiler by a pump, and heat is exchanged with high-temperature circulating gas to form steam. On the other hand, the heat medium that has recovered the heat of the circulating gas in the first heat exchanger reaches the second heat exchanger and heats the boiler feed water. Thereafter, the heat medium is circulated again to the first heat exchanger by a circulation pump.
[0006]
[Patent Document 1]
Japanese Patent Laid-Open No. 3-11909
[Problems to be solved by the invention]
In the technique disclosed in FIG. 2 and Patent Document 1, a heat exchanger is installed in the circulation duct, and heat is exchanged between the sensible heat of the circulation gas in the circulation duct and the cooling water to lower the circulation gas temperature. Yes, we are trying to raise the cooling water temperature, but since the heat exchanger is installed in the circulation duct, the corrosion problem of the heat exchanger due to the circulation gas cannot be solved. That is, since the amount of gas flowing in the circulation duct varies depending on the amount of coke input and the operating conditions, it is difficult to adjust the temperature to prevent condensation corrosion. Therefore, the current situation is that the operation is performed with the circulating gas temperature kept at the dew condensation temperature or more as in the conventional case.
[0008]
In addition, even when heat exchange is performed by a closed circulation path, when a heat medium is enclosed in the closed circulation path and this heat medium is circulated and used, the heat medium is sealed due to deterioration of the heat medium or the closed type. In order to cool the circulating gas temperature of about 180 ° C to about 130 ° C, a large-scale device is required. I never did.
[0009]
Therefore, the problem to be solved by the present invention is a method of supplying water to a boiler of a coke dry fire extinguishing facility that does not cause condensation corrosion, can reduce the cooling temperature to the cooling tower, and can be an inexpensive facility, and It is to provide a water supply device.
[0010]
[Means for Solving the Problems]
The method of supplying water to the boiler of the coke dry fire extinguishing system according to the present invention is to supply red hot coke into a cooling tower, blow in an inert gas into the cooling tower to exchange heat, and pass the inert gas after heat exchange to the boiler. The waste water is recovered by exchanging heat with the cooling water supplied to the boiler from the water supply tank, and the recovered inert gas is reintroduced into the cooling tower and circulated. In the method, the cooling water from the water supply tank is supplied to the deaerator, and heat is exchanged between the cooling water sent from the deaerator and the cooling water supplied from the water tank to the deaerator. The cooling water after the heat exchange sent out from is supplied to the boiler.
[0011]
In this water supply method, the temperature of the cooling water after the heat exchange sent from the deaerator can be set to 60 ° C. or less.
[0012]
In addition, the water supply device for the boiler of the coke dry fire extinguishing equipment of the present invention, injects red hot coke into the cooling tower, blows an inert gas into the cooling tower to exchange heat, and the inert gas after the heat exchange. To the boiler of the coke dry fire extinguishing equipment, in which waste heat is recovered by exchanging heat with the cooling water supplied to the boiler from the water tank, and the recovered inert gas is again introduced into the cooling tower and circulated. In this water supply apparatus, a supply pipe for supplying the cooling water from the water supply tank to the deaerator and a water supply pipe for supplying the cooling water sent from the deaerator to the boiler are provided, and water supply heat exchange is performed on the water supply pipe. And a supply pipe from the water supply tank is connected to the water supply heat exchanger.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a flow diagram showing a configuration of a water supply device to a boiler of a coke dry fire extinguishing facility of the present invention.
[0014]
As shown in the figure, in the coke dry fire extinguishing equipment, the red hot coke charged from the upper part of the cooling tower 1 is heat-exchanged by the circulating gas and discharged from the discharge apparatus connected to the lower part of the cooling tower 1 to the outside of the system. The The gas exchanged with the sensible heat of the red hot coke is sent to the boiler 4 through the circulation duct 2 connected to the upper part of the cooling tower 1. A primary dust catcher 3 is disposed in the middle of the circulation duct 4 to remove dust such as coke powder contained in the gas. The gas from which the dust has been removed is sent to the boiler 4, and exchanges heat with the heat exchanger 5, which is disposed in the boiler 4, which includes the superheater 6, the evaporator 7, and the economizer 8, and is placed below the boiler 4. It is sent to the cooling tower 1 again from the connected circulation duct 9. A dust collector 10 and a circulation blower 11 are installed in the middle of the circulation duct 9, dust in the gas is removed again by the dust collector 10, and the gas from which dust has been removed is sent to the cooling tower 1 by the circulation blower 11. It is supposed to be. In addition, the code | symbol 26 of FIG. 1 shows an air / water cylinder.
[0015]
On the other hand, the cooling water stored in the water supply tank 12 is supplied to the deaerator 16 through the supply pipe 14 by the degassing water supply pump 13, and the degassed cooling water is supplied through the water supply pipe 19 by the boiler water supply pump 18. The boiler 4 is supplied with water. In the supply pipe 14, a feed water heat exchanger 15 is arranged on the primary side of the deaerator 16, and the feed water heat exchanger 15 is sent to the deaerator 16 through cooling water sent from the feed water tank 12. A low-pressure steam 17 is blown into the deaerator 16 and the steam is deaerated. The deaerated cooling water is sent to the boiler 4 by the boiler feed water pump 18, but the feed water pipe 19 through which the deaerated cooling water is passed is connected to the feed water heat exchanger 15, and thereby the deaerated cooling water is supplied. The water is sent to the boiler 4 through heat exchange with the cooling water sent from the water supply tank 12.
[0016]
The temperature of the cooling water stored in the feed water tank 12 is about 20 ° C., and the temperature rises to about 65 ° C. by passing the 20 ° C. cooling water through the feed water heat exchanger 15. This 65 ° C. cooling water is sent to the deaerator 16. The deaerator 16 is degassed by low-pressure steam at about 230 ° C., and becomes cooling water at about 105 ° C. The cooling water that has risen to 105 ° C. is sent to the feed water heat exchanger 15 to exchange heat with about 20 ° C. cooling water from the feed water tank 12 and is supplied to the boiler 4 as about 60 ° C. cooling water.
[0017]
Since the temperature of the cooling water supplied to the boiler 4 is 60 ° C., the temperature of the gas sent into the boiler 4 is lowered to about 120 ° C. and discharged to the circulation duct 9 and passes through the dust collector 10. After the dust in the gas is removed by the dust collector 10, the gas is pressurized by the circulation blower 11 and sent to the cooling tower 1. The temperature of the gas sent to the cooling tower 1 rises by about 10 ° C. to 130 ° C. due to the pressure increase of the circulation blower 11.
[0018]
Further, in order to keep the temperature of the coolant supplied to the boiler 4 at about 60 ° C., a flow rate adjusting valve 25 is provided in the supply pipe 14 from the water supply tank 12. The flow rate adjusting valve 25 can adjust the temperature of the degassed cooling water discharged from the deaerator 16.
[0019]
【The invention's effect】
As mentioned above, according to this invention, since the temperature of the cooling water supplied to a boiler can be lowered | hung, the inside of a boiler can be made compact. Further, since the gas temperature can be lowered, the cooling capacity in the cooling tower can be increased. Also. Since no heat exchanger is installed in the circulation duct, condensation corrosion of the heat exchanger can be prevented.
[Brief description of the drawings]
FIG. 1 is a flow diagram showing the configuration of a water supply apparatus for a boiler of a coke dry fire extinguishing facility according to the present invention.
FIG. 2 is a flow diagram showing a configuration of a heat recovery device of a conventional coke dry fire extinguishing facility.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cooling tower 2 Circulation duct 3 Primary dust catcher 4 Boiler 5 Heat exchanger 6 Superheater 7 Evaporator 8 Carving saver 9 Circulation duct 10 Dust collector 11 Circulation blower 12 Water supply tank 13 Deaeration feed pump 14 Supply pipe 15 Feed water heat Exchanger 16 Deaerator 17 Low pressure steam 18 Boiler feed pump 19 Feed water pipe 20 Feed water heat exchanger 21 Feed pipe 22 Drain pipe 23 Feed water preheater 24 Feed water pipe 25 Flow control valve 26 Air / water cylinder

Claims (3)

Red hot coke is put into the cooling tower, an inert gas is blown into the cooling tower to exchange heat, and the inert gas after the heat exchange is sent to the boiler to supply the boiler with cooling water and Supplying cooling water from the water tank to the deaerator in the method of supplying water to the boiler of the coke dry fire extinguishing equipment, where waste heat is recovered by heat exchange and the recovered inert gas is reintroduced into the cooling tower and circulated. Heat exchange between the cooling water sent from the deaerator and the cooling water supplied from the water supply tank to the deaerator, and supplying the cooled cooling water sent from the deaerator to the boiler A method for supplying water to a boiler of a coke dry fire extinguishing system characterized by The method for supplying water to a boiler of a coke dry fire extinguishing system according to claim 1, wherein the temperature of the cooling water after heat exchange sent from the deaerator is set to 60 ° C or lower. Red hot coke is put into the cooling tower, an inert gas is blown into the cooling tower to exchange heat, and the inert gas after the heat exchange is sent to the boiler to supply the boiler with cooling water and Supplying cooling water from the water tank to the deaerator in the water supply system to the boiler of the coke dry fire extinguishing equipment that recovers waste heat by heat exchange and recirculates the recovered inert gas into the cooling tower. And a water supply pipe for supplying the cooling water sent from the deaerator to the boiler, a water supply heat exchanger is provided in the water supply pipe, and the water supply heat exchanger is connected to the water supply tank from the water supply tank. A water supply device for a boiler of a coke dry fire extinguishing system, characterized by connecting supply pipes.

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