JPS6115357B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for extracting the retained heat of exhaust gas generated from a metallurgical furnace as continuous and constant thermal energy and supplying it to thermal energy utilization equipment in steel manufacturing equipment that is operated intermittently. This invention relates to a metallurgical furnace exhaust gas treatment device. The gas generated from the metallurgical furnace is cooled by a cooler 2, as shown in FIG.

Further, in steelmaking equipment, there is a time when oxygen is injected into the metallurgical furnace 1 for refining (hereinafter referred to as blowing), and a so-called non-blowing time when blowing is stopped after completion of refining and the molten pig iron in the metallurgical furnace is taken out.

In this steelmaking process, a large amount of high-temperature gas is generated from the metallurgical furnace during blowing, and this gas is not generated during non-blowing.

Therefore, the temperature of the cooling water circulating in the water-cooled wall of the cooler changes between blowing and non-blowing.

Further, the heat retained in the gas generated from the metallurgical furnace is recovered by cooling water circulating in the cooler.

In this way, the conventional technology for extracting the retained heat of the gas generated from the metallurgical furnace as continuous and constant thermal energy via cooling water involves installing a high-temperature water tank and a low-temperature water tank in the cooling water circulation system of the metallurgical furnace. The high-temperature water during blowing was stored in a high-temperature water tank, and the low-temperature water during non-blowing was stored in a low-temperature water tank. As a result, the high-temperature water required for thermal energy users (hereinafter referred to as thermal energy utilization equipment) is limited to the high-temperature water stored in the high-temperature water tank during blowing, and is sufficient to cool the entire metallurgical furnace cooling water circulation system. It was not possible to utilize the heat held by water.

The present invention was made in view of this situation. That is, in the present invention, the gas stored in the gas holder during blowing is supplied into the cooler through the gas supply system during non-blowing, is combusted, and the temperature of the cooling water at the outlet of the cooler is controlled by the combustion gas. It is characterized by raising the temperature and supplying the entire amount of cooling water to the thermal energy utilization equipment.

The details will be explained below using examples. Already the first
As explained in the figure, the metallurgical furnace 1 during blowing
After the CO gas is cooled in the cooler 2, the dust remover 3,
When the gas CO concentration is low and when the gas supplied from the gas holder is combusted in the cooler, the CO is removed through the dispersion tower 7 and released into the air. % gas is switched by a switching valve 6 and stored in a gas holder 9 via a flow path 8. Figures 2 and 3
4 and 5 show the implementation of the present application, in which the metallurgical furnace exhaust gas treatment apparatus shown in FIG. 1 is divided at the cooler, and only the parts related to the present application are shown. First, the parts common to the embodiments shown in FIGS. 2, 3, 4, and 5 will be explained. In the figures, the cooler 2 provided above the metallurgical furnace 1 is composed of a water-cooled wall, and the cooling water is A circulation pump 10 circulates the water within the water cooling wall of the cooler. 11
is a gas supply system for supplying gas from the gas holder 9 to the cooler 2. Reference numeral 14 denotes an air pipe through which air necessary for burning the gas sent from the gas holder 9 into the cooler 2 is sent from the air supply device 15. This gas supply system 11 and air piping 14 are provided with husband and wife flow rate control valves 12 and 13, and the flow rate control valves 12 and 13 are temperature detectors that detect the gas temperature at the outlet of the cooler 2 and the cooling water temperature. It operates by signals from 16 and 17.

Next, each of the embodiments will be explained. In FIG. 2, the cooling water discharged from the outlet of the cooler 2 as high-pressure and high-temperature water flows into a high-pressure and high-temperature water tank 19 through a flow path 18.
The heat is guided through a flow path 20 and then recovered by a thermal energy utilization facility 21, such as a high-pressure and high-temperature turbine. Furthermore, the heat-recovered cooling water flows through the flow path 22 and is recirculated to the inlet of the cooler 2 by the circulation pump 10, forming one closed cooling water circulation circuit. In the high-pressure, high-temperature water tank 19, the pressure of the high-temperature cooling water is increased by an inert gas, for example, a gas such as _N2 , thereby increasing the thermal efficiency of the thermal energy utilization equipment 21. Next, in Figure 3,
The cooling water, which becomes high-pressure and high-temperature water from the outlet of the cooler 2, is led to the steam reservoir 23 through the flow path 18, and the cooling water accumulated at the bottom of the steam reservoir 23 flows through the flow path 26 by the circulation pump 10. Recirculated to cooler 2 inlet,
It constitutes one closed cooling water circulation circuit. In the steam reservoir 23, the cooling water flash evaporates, and this steam flows through a flow path 24 and is led to a thermal energy utilization facility 21, such as a steam turbine, where heat is recovered, and is condensed in a condenser 25. , the liquid flows through the flow path 24 and returns to the steam reservoir 23 by the transfer pump 35 again.

In FIG. 4, the cooling water that has come out of the cooler 2 as high-pressure high-temperature water is led to a high-temperature water tank 27 through a flow path 18, and is then passed through a flow path 28 to a thermal energy utilization facility 21, such as a steam turbine. Heat is recovered by being guided by Furthermore, the heat-recovered cooling water flows through the flow path 29 and is recirculated by the circulation pump 10 to the inlet of the cooler 2, forming one closed cooling water circulation circuit. Note that high-temperature cooling water is temporarily stored in the high-temperature water tank 27 and supplied to the thermal energy utilization device 21 as cooling water at a required constant temperature. The embodiment shown in FIG. 5 further includes a branch flow path 30 in addition to the cooling water circulation path of the embodiment shown in FIG. It is used for both time and time.

To explain the additional parts in the figure, this additional part is a circuit when the thermal energy utilization equipment 21 is not used, and 30 is a flow path branched in the middle of the flow path 18, which connects to the low temperature water tank 31. The cooling water flows from the low-temperature water tank 31 through the flow path 32 and is recirculated to the inlet of the cooler 2 by the circulation pump 10, forming one closed cooling water circulation circuit. In addition, during blowing, when the thermal energy utilization equipment 21 is not used, the temperature of the cooling water is lowered by a heat exchanger 36 provided in the flow path 32 to reach the required cooling water temperature. . 33 and 34 are switching valves provided in the flow paths 18 and 30, and when the thermal energy utilization equipment 21 is used, the switching valve 33 is opened and the switching valve 34 is closed. When the thermal energy utilization equipment 21 is not used, the switching valve 33 is closed and the switching valve 34 is opened. Further, in this embodiment, a transfer pump 37 is provided in the middle of the flow path 28 from the high temperature water tank 27 to the thermal energy utilization equipment 21.

In the embodiment of the present invention configured as described above, CO gas generated from the metallurgical furnace 1 during blowing is cooled by the cooler 2 and removed by the dust removers 3 and 4, while being attracted by the blower 5. , gas with high CO% is stored in the gas holder 9 as valuable gas.

When the gas stored in this way is not blown, the flow rate control valve 12 is operated by the signals from the gas temperature detector 16 and the cooling water temperature detector 17 to adjust the gas flow rate and supply the gas. The system 11 supplies air to the cooler 2, and from the air supply device 15, the control valve 13 operates in response to the signals from the temperature detectors 16 and 17, and the air flow is adjusted through the air pipe 14. air is supplied to the cooler 2 to cause combustion. In this way, the temperature of the cooling water at the outlet of the cooler 2 is kept constant regardless of blowing or non-blowing. In FIG. 2, the cooling water that has reached a constant temperature at the outlet of the cooler 2 flows through a flow path 18 and is led to a high-pressure, high-temperature water tank 19, where it is brought to a predetermined pressure with an inert gas such as _N2 . It is pressurized and becomes the constant high pressure and high temperature water required by the thermal energy utilization equipment 21,
Thermal energy utilization equipment 21, for example, is supplied to a high pressure and high temperature turbine. Next, the cooling water is heat-recovered by the thermal energy utilization equipment 21 and then passed through the flow path 22.
is recycled into the cooler 2 by the circulation pump 10.

In FIG. 3, cooling water flows through channel 18 and is led to steam reservoir 23. In FIG. The cooling water that has entered the steam reservoir 23 flash-evaporates and immediately turns into steam, which flows through a flow path 24 and is supplied to the thermal energy utilization equipment 21, such as a steam turbine, as thermal energy required by the thermal energy utilization equipment 21. The cooling water that has turned into steam is subjected to heat recovery by the thermal energy utilization equipment 21 and then condensed by the condenser 25.
It is transferred by the transfer pump 35, returns to the steam reservoir 23 via the flow path 24, flows through the flow path 26, and is transferred to the circulation pump 1.
0 to the cooler 2.

In FIG. 4, the cooling water flows through the channel 18 and is led to the high-temperature water tank 27, where it is temporarily stored and used as cooling water having the thermal energy required by the thermal energy utilization equipment 21,
For example, it is supplied to a steam turbine or the like through a flow path 28. The cooling water whose heat has been recovered by the thermal energy utilization equipment 21 flows through the flow path 29 and is recirculated to the cooler 2 by the circulation pump 10.

In FIG. 5, when the thermal energy utilization equipment 21 is not used, combustion by the gas supply from the gas holder 9 is stopped, and therefore, the cooling water at the outlet of the cooler becomes low-temperature water and flows into the flow path 18. In this case, the switching valve 33 is closed and the switching valve 34 is open, so the cooling water flows from the flow path 18 to the branch flow path 30, is stored in the low temperature water tank 31, and is circulated through the flow path 32. Recirculation to cooler 2 by pump 10. In addition, during blowing, thermal energy utilization equipment 2
1 is not used, the cooling water is cooled down by the heat exchanger 36 to the required cooling water temperature and recycled to the cooler 2. Next, the use of the thermal energy utilization equipment 21 is the same as in the embodiment shown in FIG. 4, so a description thereof will be omitted.

In this way, in the embodiment shown in FIG. 5, the switching valve 3
3 and 34 are activated to allow cooling water to flow through the two circulation circuits.

As detailed above, according to the present invention, a gas supply system connected to a gas holder at the inlet of a gas cooler;
An air supply system is installed to combust the gas, and the gas is combusted within the cooler while adjusting the amount of gas so that the temperature of the cooling water at the outlet of the cooler remains constant during non-blowing. Since the pressurized high-temperature water, steam, or hot water is supplied to the thermal energy utilization equipment, the entire amount of cooling water can be led to the thermal energy utilization equipment, and the total thermal energy held by the cooling water can be used. The effect is great because it can be done.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing the entire metallurgical furnace exhaust gas treatment equipment, Figs. 2, 3, 4, and 5 show examples;
FIG. 2 is a diagram illustrating only the parts related to the invention out of the metallurgical furnace exhaust gas treatment apparatus shown in the figure for easy understanding. DESCRIPTION OF SYMBOLS 1...Metallurgical furnace, 2...Cooler, 9...Gas holder, 10...Circulation pump, 11...Gas supply system conduit, 12, 13...Flow rate control valve, 14...Air piping, 15... ...Air supply device, 16...Gas temperature detector, 17...Cooling water temperature detector, 18,2
0, 22, 24, 26, 28, 29, 30, 32
...Flow path, 19...High pressure high temperature water tank, 21...
Thermal energy utilization device, 23... Steam reservoir, 25...
... Condenser, 27 ... High temperature water tank, 31 ... Low temperature water tank, 33, 34 ... Switching valve, 35, 37 ...
...transfer pump, 36...heat exchanger.

Claims (1)

[Claims] 1. In a metallurgical furnace exhaust gas treatment device that cools and removes dust from the gas generated from a metallurgical furnace and collects it as a valuable gas in a gas holder, a gas supply system connected to the gas holder is provided at the inlet of the gas cooler, while a combustion An air supply system for supplying air for use is provided, and a flow rate control valve that is operated depending on the cooling water temperature and gas temperature at the outlet of the cooler is provided between the gas supply system and the air supply system, so that the gas flow during non-blowing is provided. The gas in the holder is supplied into the cooler, combusted in the cooler, the cooling water temperature at the outlet of the cooler is adjusted to a constant temperature, the cooling water is supplied to the thermal energy utilization equipment, and the thermal energy utilization equipment is activated. A metallurgical furnace exhaust gas treatment device that continuously recovers a certain amount of thermal energy, characterized in that the cooling water that comes out is guided to a cooler.