Flue gas waste heat utilization system for blast furnace hot blast stove of iron making plant

Abstract

The utility model relates to the field of iron mill blast furnace hot blast stove flue gas treatment, in particular to an iron mill blast furnace hot blast stove flue gas waste heat utilization system. The system comprises a denitration reactor, a waste heat boiler, a water treatment station, a blowdown flash tank and a generator set. Heat of flue gas generated by an iron making plant is utilized, raw water is softened and deoxidized and then supplied to a waste heat boiler, superheated steam is generated after temperature and pressure increase, and the superheated steam enters a power generation device for power generation, enters a heat supply pipe network for supplying heat to a plant area or enters the heat supply pipe network for production. Wastewater generated by the boiler enters the blowdown expansion device, part of saturated steam is discharged to the atmosphere, and part of wastewater enters the water treatment station and is used for water supply of the waste heat boiler after being treated. The high-temperature flue gas serves as a heat source of the waste heat boiler to generate superheated steam, and the superheated steam enters the generator set for power generation work.

Description

Technical Field

[0001] The present application relates to the field of blast furnace hot blast stove flue gas treatment in an ironmaking plant, and specifically to a blast furnace hot blast stove flue gas waste heat utilization system in an ironmaking plant. Background Art

[0002] At present, the flue gas generated by the hot blast furnace of the iron smelting plant is discharged from the chimney after being denitrified and blown by the booster fan. The high-temperature clean flue gas generated by the hot blast furnace of the iron smelting plant is not utilized, and there is still room for waste heat utilization in the flue gas. Utility Model Content

[0003] The purpose of this application is to provide a system for utilizing waste heat from flue gas of a hot blast stove in a blast furnace of an ironmaking plant to reduce energy waste.

[0004] The ironmaking plant blast furnace hot blast furnace flue gas waste heat utilization system according to the present application includes a denitration reactor, a waste heat boiler, a water treatment station, a sewage expansion tank, and a generator set, wherein:

[0005] According to the flue gas flow direction, the inlet gas pipeline of the denitrification reactor is connected to the hot blast furnace of the ironmaking plant, and the outlet gas pipeline of the denitrification reactor is divided into a main flue and a bypass, the main flue is connected to the chimney, and the bypass is connected to the waste heat boiler;

[0006] According to the flow direction of the raw water, the water outlet of the water treatment station is connected with the water inlet of the waste heat boiler through a pipeline;

[0007] The hot steam outlet of the waste heat boiler is connected to the hot steam inlet of the generator set, and the waste water outlet of the waste heat boiler is connected to the blowdown expansion tank;

[0008] The wastewater outlet of the blowdown expansion tank is connected to the water treatment station;

[0009] The hot steam outlet of the generator set is connected to the water treatment station through a pipeline.

[0010] According to the ironmaking plant blast furnace hot blast stove flue gas waste heat utilization system of the present application, a control valve and an induced draft fan are sequentially provided on the pipeline connecting the denitration reactor and the chimney.

[0011] According to the ironmaking plant blast furnace hot blast stove flue gas waste heat utilization system of the present application, the flue gas outlet of the waste heat boiler is connected to the main flue.

[0012] According to the ironmaking plant blast furnace hot blast stove flue gas waste heat utilization system of the present application, the control valve is a butterfly valve that can control the opening.

[0013] According to the flue gas utilization system for the hot blast stove of the blast furnace of the ironmaking plant of the present application, a condenser is provided between the generator set and the water treatment station.

[0014] According to the flue gas utilization system for the hot blast stove of the blast furnace of the ironmaking plant of the present application, a water pump is provided on the connecting pipeline between the water outlet of the water treatment station and the water inlet of the waste heat boiler.

[0015] According to the flue gas utilization system for the hot blast stove of the blast furnace of the ironmaking plant of the present application, a condenser is provided on the pipeline connecting the hot steam outlet of the generator set and the water treatment station.

[0016] Beneficial technical effects of this application:

[0017] By utilizing the waste heat utilization system of the hot blast furnace flue gas in the ironmaking plant of the present application, the clean flue gas treated by the ironmaking plant is passed into the waste heat boiler, and after heat exchange with the waste heat boiler, it is blown by the booster fan and then discharged from the chimney. The steam generated by the heat exchange is used by the krypton steam turbine generator set to generate electricity, and the excess steam enters the thermal network and can be used for factory production or heating the factory and surrounding areas in winter. The newly extracted raw water enters the pipeline through the water pump and enters the water treatment station through the pipeline. The raw water enters the waste heat boiler after being treated in the water treatment station. The high-temperature wastewater generated by the boiler enters the sewage expansion tank, and the sewage expansion tank enters the water treatment station after being cooled and decompressed. The steam generated by the generator set is condensed by the condenser and enters the water treatment station. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the structure of the ironmaking plant blast furnace hot blast stove flue gas waste heat utilization system of this application. DETAILED DESCRIPTION

[0019] The utility model proposes a waste heat utilization system for the flue gas of the hot blast stove of the blast furnace of an ironmaking plant, which utilizes the heat of the flue gas generated by the ironmaking plant, softens and deoxidizes the raw water, and supplies it to the waste heat boiler, generates superheated steam after temperature and pressure increase, and enters the power generation device to generate electricity, or enters the thermal network to heat the factory area. The waste water generated by the boiler enters the sewage expansion device, and part of the saturated steam is discharged to the atmosphere, and part of the waste water enters the water treatment station, and is used for water supply to the waste heat boiler after treatment. The high-temperature flue gas is used as the heat source of the waste heat boiler to generate superheated steam, and the superheated steam enters the generator set to generate electricity.

[0020] The following is a detailed description of the design scheme with reference to the accompanying drawings:

[0021] like Figure 1 As shown, the flue gas utilization system for the hot blast stove of the blast furnace of the ironmaking plant of the present application includes: a control valve 1, a waste heat boiler 2, a sewage expansion tank 3, a water treatment station 4, a condenser 5, a water pump 6, a generator set 7, and a denitrification reactor 9.

[0022] The clean flue gas treated by the denitration reactor enters the waste heat utilization system through a pipeline, exchanges heat with the waste heat boiler, and is discharged into a chimney under the blowing of an induced draft fan.

[0023] The original flue gas becomes clean flue gas after denitration treatment in the denitration reactor 9 , part of the clean flue gas enters the waste heat boiler 2 through the bypass, and the other part of the clean flue gas enters the main flue and is discharged into the atmosphere under the blowing of the control valve 1 and the induced draft fan 8 .

[0024] The raw water is pumped by the water pump 6 and then enters the water treatment station 4. After being treated by the water treatment station 4, it enters the waste heat boiler 2 to generate superheated steam and enters the generator set 7. The waste water generated by the waste heat boiler 2 enters the sewage expansion tank 3. The sewage expansion tank 3 treats the waste water and then enters the water treatment station 4. The superheated steam generated by the generator set 7 is condensed by the condenser 5 and then enters the water treatment station 4.

[0025] The iron-making plant generates a large amount of high-temperature flue gas during the production process. The waste heat generated by the clean flue gas after denitration treatment is utilized through the flue gas utilization system for the hot blast furnace of the iron-making plant in this application. The flue gas is introduced into the flue gas utilization system, and the raw water enters the waste heat boiler after treatment. The high-temperature flue gas is used as the heat source of the waste heat boiler to heat and generate superheated steam. The superheated steam enters the generator set to generate electricity. The waste water generated by the waste heat boiler enters the sewage expansion tank through a pipeline, and the sewage expansion tank releases the waste steam on the spot. The waste water generated by the sewage expansion tank directly enters the water treatment station. The water source refers to tap water from the urban pipe network or untreated natural water.

[0026] The above specific embodiments further illustrate the purpose and technical solutions of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A system for utilizing waste heat from flue gas of a hot blast stove in a blast furnace of an ironmaking plant, characterized in that: The system includes a denitration reactor, a waste heat boiler, a water treatment station, a sewage expansion tank, and a generator set, wherein: The inlet gas pipeline of the denitration reactor is connected to the hot blast furnace of the ironmaking plant, and the outlet gas pipeline of the denitration reactor is divided into a main flue and a bypass, the main flue is connected to the chimney, and the bypass is connected to the waste heat boiler; The water outlet of the water treatment station is connected to the water inlet of the waste heat boiler through a pipeline; The hot steam outlet of the waste heat boiler is connected to the hot steam inlet of the generator set, and the waste water outlet of the waste heat boiler is connected to the blowdown expansion tank; The wastewater outlet of the blowdown expansion tank is connected to the water treatment station; The hot steam outlet of the generator set is connected to the water treatment station through a pipeline.

2. The ironmaking plant blast furnace hot blast stove flue gas waste heat utilization system according to claim 1, characterized in that: A control valve and an induced draft fan are arranged in sequence on the pipeline connecting the denitration reactor and the chimney.

3. The ironmaking plant blast furnace hot blast stove flue gas waste heat utilization system according to claim 1, characterized in that: The flue gas outlet of the waste heat boiler is communicated with the main flue.

4. The ironmaking plant blast furnace hot blast stove flue gas waste heat utilization system according to claim 2, characterized in that: The control valve is a butterfly valve.

5. The ironmaking plant blast furnace hot blast stove flue gas waste heat utilization system according to claim 1, characterized in that: A condenser is provided on the connecting pipeline between the hot steam outlet of the generator set and the water treatment station.

6. The ironmaking plant blast furnace hot blast stove flue gas waste heat utilization system according to claim 1, characterized in that: A water pump is provided on the connecting pipeline between the water outlet of the water treatment station and the water inlet of the waste heat boiler.

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