JP2004075743A - Cdq gas-circulating method and system therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coke dry quencher (CDQ) gas-circulating method, by which CDQ can be started up with a circulation blower driven with a steam turbine used in a steady-state operation without using an electrically driven small circulation blower, when CDQ is started up, and to provide a gas circulation system having a simplified installation. <P>SOLUTION: This CDQ gas-circulating method comprising subjecting red heat coke charged in a CDQ main body 1 and an inert gas charged from the lower portion of the CDQ main body 1 to a heat exchange treatment, recovering the sensible heat of the inert gas in a boiler 4 after the heat exchange treatment, again charging and circulating the cooled inert gas into the CDQ main body 1 with a circulation blower 5 is characterized by using steam as a driving source for driving the circulation blower 5, introducing the steam from a separately disposed steam supply source 18, when CDQ is started up, and introducing the steam from a bypass pipe 17 branched from a steam pipe 13 from the boiler 4, when the start-up of the CDQ is finished. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a circulating gas circulation system of a coke dry quencher (herein, referred to as CDQ), which uses steam generated by a boiler and steam supplied from a steam supply source as a driving source of a circulating blower. The present invention relates to a steam-driven CDQ circulating air blowing method and a system thereof that are switched and used.
[0002]
[Prior art]
In the CDQ, red hot coke is charged into the pre-chamber of the CDQ main body, lowered into the cooling chamber, and an inert gas, which is a cooling gas supplied to the cooling chamber, exchanges heat with the red hot coke to recover the heat of the red hot coke. After introducing an inert gas into the boiler and exchanging heat, the circulation gas is sent again to the cooling chamber by a circulation blower and circulated. The steam obtained by heat exchange in the boiler is sent to a generator and collected as electric energy.
[0003]
In order to drive a circulating blower for pumping an inert gas, for example, a steam turbine utilizing a part of steam generated in a boiler is used as described in JP-A-57-190079. . At the time of startup, steam for driving the steam turbine is not obtained, so it is blown by an electrically driven small circulation blower driven by a separately provided small motor, and when a predetermined amount of steam is generated, the circulation blower is driven by the steam turbine And drive.
[0004]
[Problems to be solved by the invention]
However, when a circulation blower driven by a steam turbine is employed, a facility for pumping inert gas with an electrically driven small circulation blower is required until a predetermined amount of steam is generated at startup, which complicates the system. was there.
[0005]
Therefore, the problem to be solved by the present invention is to provide a method for circulating CDQ that can be started by a steam turbine driven circulating blower used in a steady operation without using an electrically driven small circulating blower at startup. Another object of the present invention is to provide a circulation ventilation system with simplified equipment.
[0006]
[Means for Solving the Problems]
The method for circulating and blowing CDQ of the present invention exchanges heat between red hot coke charged in a CDQ main body and an inert gas introduced from below the CDQ main body to reduce the sensible heat of the inert gas after the heat exchange. In the method of circulating the CDQ, in which the inert gas cooled by the sensible heat recovery of the boiler is introduced into the CDQ body again by the circulating blower and circulated, the driving source for driving the circulating blower is steam, When the CDQ is started, steam is introduced from a separately provided steam supply source, and after completion of the CDQ, steam is introduced from a bypass pipe provided in a steam pipe from the boiler.
[0007]
In addition, the CDQ circulation ventilation system of the present invention exchanges heat between the glow coke charged into the CDQ main body and the inert gas introduced from below the CDQ main body, and expresses the inert gas after the heat exchange. In a CDQ circulating air blowing system in which heat is recovered by a boiler and the inert gas cooled by the sensible heat recovery of the boiler is again introduced into the CDQ body by a circulating blower and circulated, steam is supplied to a steam turbine for driving a circulating blower. A bypass pipe to be supplied is branched from a steam pipe from the boiler, and a steam supply pipe to supply steam from a separately provided steam supply source is connected to the steam pipe.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a flow chart showing an example of the CDQ circulation air blowing system of the present invention. The upper part of the CDQ main body 1 which cools by charging red hot coke and exchanging heat with an inert gas as a cooling gas is connected to a boiler 4 by an exhaust duct 3 provided with a dust remover 2. Further, the boiler 4 is connected to a lower portion of the CDQ main body 1 by circulation ducts 6 and 7 via a circulation blower 5. By this connection, the high-temperature inert gas heat-exchanged with the red hot coke in the CDQ main body 1 is exhausted from the CDQ main body 1, introduced into the boiler 4 through the exhaust duct 2, cooled by heat exchange, and circulated by the circulation blower 5. An inert gas circulation path, which is introduced into the CDQ main body 1 through the ducts 6 and 7, is formed.
[0009]
A heat transfer tube 8 is provided in the boiler 4, and water is supplied to the heat transfer tube 8 from water supply tubes 10 and 11 connected to a tank 9 by a water supply pump 12. The water that has flowed into the heat transfer tube 8 is discharged from the CDQ main body 1 and heat-exchanged by the high-temperature inert gas introduced into the boiler 4 to become steam, and the steam is generated through the steam pipe 13 connected to the heat transfer tube 8. The steam sent to the facility 14 and leaving the power generation facility 14 is condensed by the condenser 15 and flows into the tank 9.
[0010]
The circulation blower 5 is driven by a steam turbine 16. The steam turbine 16 is driven by steam supplied through a bypass pipe 17 branched from the steam pipe 13.
[0011]
A steam supply pipe 20 having an on-off valve 19 connected to another steam supply source 18 is connected to the steam pipe 13 to supply steam to a steam turbine 16 that drives the circulation blower 5 when the CDQ main body 1 is started up. I have. The steam supply pipe 20 is provided between a switching valve 21 provided on the boiler 4 side of the steam pipe 13 and a shutoff valve 22 provided on the power generation facility 14 side to supply steam from the steam supply source 18 to the bypass pipe 17. Connect to In addition, a radiation pipe 24 provided with a radiation valve 23 is connected to the steam pipe 13 between the switching valve 21 and the boiler 4 side in order to diffuse steam.
[0012]
The low-pressure steam that has exited the steam turbine 16 that drives the circulation blower 5 is sent to a raw material drying device 26 by a low-pressure steam pipe 25, is used for drying the raw material, is cooled and becomes water, and the water is returned to the tank 9.
[0013]
Next, the operation of the CDQ of the present invention will be described. When the CDQ is started, the switching valve 21 and the shutoff valve 22 of the steam pipe 13 are closed, and the dissipation valve 23 is opened. Thereafter, when the on-off valve 19 of the steam supply pipe 20 is opened, the steam from the steam supply source 18 drives the steam turbine 16 through the steam supply pipe 20, the steam pipe 13, and the bypass pipe 17, and exits the steam turbine 16. The low-pressure steam is cooled and returned to the tank 9 as water, and the water introduced from the tank 9 to the heat transfer tube 8 via the water supply pipes 10 and 11 is converted to steam and diffused from the diffusion pipe 24 via the steam pipe 13. Is done.
[0014]
At the time of startup, the inert gas is sent to the CDQ main body 1 by driving the steam turbine 16 by the supply of steam from the steam supply source 18 and rotating the circulation blower 5, and the inert gas is exchanged with red-hot coke. The gas is exhausted from the CDQ main body 1, introduced into the boiler 4 via the exhaust duct 3, cooled by heat exchange, and introduced into the CDQ main body 1 via the circulation ducts 6 and 7 by the circulation blower 5. FIG. 2 is a graph showing the relationship between the steam rise temperature and time. As the inert gas is circulated in the inert gas circulation path by the circulation blower, the temperature of the inert gas rises, and as shown in the graph of FIG. When the temperature reaches about 800 ° C., the temperature of the steam generated from the heat transfer tube 8 increases, and the amount of steam required for the steam turbine 16 and the power generation equipment 14 is generated. At this time, when the switching valve 21 and the shutoff valve 22 of the steam pipe 13 are opened, the dissipation valve 23 is closed, and the opening / closing valve 19 of the steam supply pipe 20 is closed, the steam of the heat transfer pipe 8 passes through the steam pipe 13. Then, the steam flows through the power generation facility 14, and a part of the steam flows through the bypass pipe 17 to drive the steam turbine 16 and rotate the circulation blower 5 to circulate the inert gas.
[0015]
【The invention's effect】
Since a single circulation blower is used during startup and during normal operation after the startup is completed, a circulation blower dedicated to startup is not required, and the equipment is simplified as compared with the related art.
[Brief description of the drawings]
FIG. 1 is a flow chart showing an example of a CDQ circulation ventilation system of the present invention.
FIG. 2 is a graph showing a relationship between a steam rising temperature and time.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 CDQ main body 2 Dust remover 3 Exhaust duct 4 Boiler 5 Circulating blower 6, 7 Circulating duct 8 Heat transfer pipe 9 Tank 10, 11 Water feed pipe 12 Water feed pump 13 Steam pipe 14 Power generation equipment 15 Condenser 16 Steam turbine 17 Bypass pipe 18 Steam Supply source 19 Open / close valve 20 Steam supply pipe 21 Switching valve 22 Shutoff valve 23 Dissipation valve 24 Dissipation pipe 25 Low-pressure steam pipe 26 Raw material drying device

Claims (2)

The heat exchange is performed between the red hot coke charged into the CDQ main body and the inert gas introduced from below the CDQ main body, and the sensible heat of the inert gas after the heat exchange is recovered by the boiler, and the sensible heat of the boiler is recovered. In the method of circulating and blowing CDQ, the inert gas cooled by the recovery is again introduced into the CDQ body by the circulation blower and circulated,
The drive source for driving the circulating blower is steam, and when the CDQ is started, steam is introduced from a separately provided steam supply source. After the start of the CDQ, the steam is supplied from a bypass pipe branched from a steam pipe from a boiler. A method of circulating CDQ, which is introduced. The heat exchange is performed between the red hot coke charged into the CDQ main body and the inert gas introduced from below the CDQ main body, and the sensible heat of the inert gas after the heat exchange is recovered by the boiler, and the sensible heat of the boiler is recovered. In a CDQ circulating air blowing system in which the inert gas cooled by the recovery is introduced again into the CDQ main body by a circulation blower and circulated,
A bypass pipe for supplying steam to a steam turbine for driving a circulation blower is branched from a steam pipe from the boiler, and a steam supply pipe for supplying steam from a separately provided steam supply source is connected to the steam pipe. CDQ circulation ventilation system.

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