JPS6115356B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a metallurgical furnace exhaust gas treatment device that continuously extracts heat retained in exhaust gas generated from a metallurgical furnace as constant thermal energy in steelmaking equipment that is operated intermittently. .

The gas generated from the metallurgical furnace is cooled by a cooler 2 as shown in FIG.

In addition, the steelmaking equipment is connected from the oxygen injection lance 7 to the metallurgical furnace 1.
There is a so-called non-blowing time in which oxygen is blown into the metallurgical furnace for refining (hereinafter referred to as blowing), and after the refining is completed, blowing is stopped 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 within the water-cooled wall of the cooler changes between during blowing and during 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 constant thermal energy through cooling water is to install 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 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 the thermal energy user (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 the entire amount of cooling water in the metallurgical reactor cooling water circulation system. It was not possible to utilize the retained heat.

The present invention has been proposed in view of the actual situation. That is, in the present invention, gas stored in a gas holder during blowing is combusted by passing through an oxygen blowing lance into a cooler during non-blowing, and the temperature of the cooling water at the outlet of the cooler is raised by this combustion gas. The present invention is characterized in that cooling water at a temperature required by thermal energy utilization equipment is continuously supplied.

The details will be explained below using examples. As already explained in Fig. 1, the CO generated in the metallurgical furnace 1
After the gas is cooled by the cooler 2, dust is removed by the dust remover 18 and stored in the gas holder 14 as a valuable gas.

FIG. 2 is an embodiment of the present invention, 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 invention are shown.

In the figure, a cooler 2 installed above a metallurgical furnace 1
is composed of a water-cooled wall, and the cooling water inlet and outlet to this water-cooled wall are connected with a pipe 4 to form a cooling water circulation circuit for the cooler 2, and the cooling water is supplied to the cooler by a circulation pump 3. The water is circulated within the water-cooled walls of No. 2. Also, the cooler 2 of this cooling water circulation circuit
A thermal energy utilization equipment 19 (for example, a steam turbine, etc.) is connected by a conduit 20 branched from the outlet of the steam turbine. In the figure, 7 is an oxygen injection lance (or sub-lance) for blowing oxygen into the metallurgical furnace 1, and this oxygen injection lance 7 is connected to an oxygen supply pipe 2.
1 is connected, and the oxygen supplied from here passes through an oxygen supply path provided in the oxygen blowing lance 7 and blows out from its tip. Since this oxygen blowing lance 7 is exposed to high temperatures, it has a heat-resistant structure such as water cooling.

Next, 13 in the figure is a gas supply system for supplying the gas in the gas holder 14 into the cooler 2 through the oxygen blowing lance 7, which connects the gas holder 14 (in this embodiment, the inlet of the gas holder 14) and the It is connected to an oxygen supply system 21. Reference numerals 8 and 9 indicate switching valves. During blowing, switching valve 8 is opened and switching valve 9 is closed to supply oxygen into the metallurgical furnace 1 through the oxygen injection lance 7. During non-blowing, switching valve 8 is closed. , 9 is opened to supply the gas in the gas holder 14 to the oxygen blowing lance 7.
It is designed to be supplied into the cooler 2 through. Reference numeral 12 denotes an air pipe for supplying air necessary for burning the gas supplied into the cooler 2 from the gas holder 14. This air pipe 12
and the gas supply system 13 have flow rate control valves 10 and 1, respectively.
1 is provided, and these flow rate control valves 10 and 11 are operated by signals from temperature detectors 5 and 6 that detect the outlet cooling water outlet temperature and gas temperature of the cooler 2.

In the figure, 15 is a water seal valve, 17 is a blower, and 16 is a chimney, and by operating the switching valve 22, the low CO% gas generated from the metallurgical furnace 1 and the gas holder 14 are removed from the cooler 2. The combustion gas produced by burning the gas supplied to the metallurgical furnace 1 is released, and the gas with a high CO concentration generated from the metallurgical furnace 1 is stored in the gas holder 14 as a valuable gas by operating the switching valve 22.

In the embodiment of the present invention configured as described above, when blowing, after inserting the oxygen injection lance 7 into the metallurgical furnace 1, the switching valve 8 is opened and the switching valve 9 is closed, so that the oxygen supply pipe 21 is Blow while blowing oxygen. During this blowing, a large amount of high temperature gas is generated from the metallurgical furnace 1.
CO gas is generated, and the temperature of the cooling water inside the water cooling wall of the cooler 2 is increased. Further, the gas at this time is stored in the gas holder 14 as a valuable gas. Next, when blowing is completed, the oxygen blowing lance 7 is pulled upward and stops when its tip is located inside the gas cooler 2. During the process of lifting the oxygen blowing lance 7, the switching valves 8 and 9 are switched, and when the oxygen blowing lance 7 is pulled up to a predetermined position, the switching valve 8 is closed and the switching valve 9 is opened. At this time, the flow rate control valve 1 is adjusted so that the outlet cooling water temperature of the cooler 2 is constant.
The flow rate is adjusted by 0 and 11 and the gas holder 1
The gas No. 4 is supplied into the cooler 2 and combusted.
This combustion gas is released from the chimney 16 by operating the switching valve 22.

As detailed above, according to the present invention, the gas supply system pipe for supplying the gas stored in the gas holder is connected to the oxygen supply pipe to the oxygen blowing lance, and the metallurgical Oxygen is supplied into the furnace, and gas is supplied into the cooler during non-blowing, respectively, through an oxygen blowing lance, and a flow rate control valve is installed in the gas supply system, as well as a flow rate control valve in the air piping. Since the amount of gas is adjusted so that the temperature of the cooling water at the outlet of the cooler remains constant, the temperature of the cooling water at the outlet of the cooler can be adjusted to a constant level even during non-blowing, and the entire amount of cooling water is heated. It is possible to continuously supply all of the thermal energy held by the cooling water to the energy utilization equipment, and also to supply the gas in the gas holder into the cooler through the oxygen blowing lance. Therefore, there is no need for a special device to supply this gas, and it can be easily implemented in existing steelmaking equipment.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing the entire metallurgical furnace exhaust gas treatment device, and Fig. 2 is an embodiment of the present invention, in which only the parts related to the present invention are extracted from the metallurgical furnace exhaust gas treatment device shown in Fig. 1. , which is an easy-to-understand diagram. 1...Metallurgical furnace, 2...Cooler, 5, 6...Temperature detector, 7...Oxygen injection lance, 8, 9...Switching valve, 10, 11...Flow rate control valve, 13...Gas supply System pipe, 14...gas holder.

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 is provided that branches off from the oxygen supply pipe of the oxygen injection lance and connects to the gas holder, and A switching valve is installed at the branch point to enable switching between the oxygen supply and gas supply to the lance, while an air supply system is installed to supply combustion air into the cooler to control the cooling water temperature and gas temperature at the cooler outlet. A flow control valve operated by the gas supply system is provided between the gas supply system and the air supply system, and the switching valve is switched during non-blowing to supply the gas in the gas holder into the cooler through the oxygen blowing lance, Burn it in a cooler,
A metallurgical furnace exhaust gas treatment device that adjusts the temperature of the cooling water at the outlet of the cooler to a certain constant temperature.