CN216935469U

CN216935469U - Sintering flue gas desulfurization and denitrification circulating system

Info

Publication number: CN216935469U
Application number: CN202220707041.4U
Authority: CN
Inventors: 刘建军; 张强; 赵恩宇; 齐超群; 李文斌; 刘斌; 郑丽丽
Original assignee: Tangshan Ruifeng Iron & Steel Group Co ltd
Current assignee: Tangshan Ruifeng Iron & Steel Group Co ltd
Priority date: 2022-03-30
Filing date: 2022-03-30
Publication date: 2022-07-12
Anticipated expiration: 2032-03-30

Abstract

The utility model discloses a sintering flue gas desulfurization and denitrification circulating system, and relates to the technical field of flue gas desulfurization and denitrification. This system includes the flue gas pipeline, SDA desulphurization unit, the heat exchanger, denitrification facility, the heating furnace, the net flue gas pipeline of denitration, electromagnetic control valve and flue gas mixing branch pipe, flue gas pipeline both ends respectively with the sintering machine, SDA desulphurization unit is connected, SDA desulphurization unit and the first access connection of heat exchanger, the first export of heat exchanger is connected with denitrification facility, denitrification facility respectively with the heating furnace, the import of heat exchanger second links to each other, the export of heat exchanger second and the net flue gas pipeline intercommunication of denitration, the net flue gas pipeline of denitration is connected with the denitration flue gas branch pipe, denitration flue gas branch pipe links to each other with electromagnetic control valve, electromagnetic control valve passes through flue gas mixing branch pipe and sintering machine flue gas pipeline intercommunication. The utility model utilizes the rapid preheating system of the denitration device, solves the problem of unstable desulfurization and denitration effects in a period of time when the sintering machine starts to produce, and ensures that the flue gas emission reaches the standard.

Description

Sintering flue gas desulfurization and denitrification circulating system

Technical Field

The utility model relates to the technical field of flue gas desulfurization and denitration, in particular to a sintering flue gas desulfurization and denitration circulating system.

Background

In recent years, in the face of severe environment protection situation, steel enterprises actively increase the environmental protection input force, and newly add and build a desulfurization and denitrification integrated sintering flue gas treatment process, so that the pollutant emission is effectively reduced, and the pollutant emission standard is ensured. However, the traditional steel enterprise production seriously pollutes the atmosphere quality, and along with the development of environmental protection production, the sintering machine in the steel enterprise frequently stops and limits production due to unqualified or standard exceeding of flue gas emission, and frequent starting and stopping of the sintering machine will inevitably cause frequent starting and stopping of desulfurization and denitrification equipment. The desulfurization and denitrification equipment is started again after being shut down and is influenced by the lower temperature of sintering flue gas, the desulfurization equipment cannot spray slurry, calcium oxide, sulfur dioxide and sulfur trioxide react to generate calcium sulfate, and the denitrification equipment cannot spray ammonia water, so that nitrogen oxides and the ammonia water react to generate ammonia water.

Generally speaking, the sintering flue gas can fully play the role of a desulfurization device when reaching more than 120 ℃, and sulfur dioxide in the flue gas is removed. Nitrogen oxides can be removed through reduction reaction of denitration equipment only when sulfur dioxide is removed to below 50 mg/Nm. And then within 2 hours from the sintering machine to start production, the desulfurization and denitrification equipment is influenced by the lower temperature of sintering flue gas, the desulfurization and denitrification effect is unstable, and even the phenomena of pollutant overproof emission and atmosphere pollution are caused.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problems, the utility model provides a sintering flue gas desulfurization and denitrification circulating system which ensures that the initial desulfurization and denitrification effect of the sintering machine during production is stable.

In order to realize the technical purpose, the utility model adopts the following scheme: the sintering flue gas desulfurization and denitrification circulating system comprises a sintering machine flue gas pipeline, an SDA (first-order-System-architecture) desulfurization device, a dust remover, a heat exchanger, a denitrification device, a heating furnace, a denitrification clean flue gas pipeline, an electromagnetic regulating valve and a flue gas mixing branch pipe, wherein the heat exchanger comprises a first inlet, a second inlet, a first outlet and a second outlet; sintering machine flue gas pipeline one end is connected with the sintering machine, the sintering machine flue gas pipeline other end is connected with SDA desulphurization unit, SDA desulphurization unit is connected with the dust remover, the first access connection of dust remover and heat exchanger, the first export of heat exchanger is connected with denitrification facility, denitrification facility respectively with the heating furnace, the import of heat exchanger second links to each other, the clean flue gas pipeline intercommunication of heat exchanger second export and denitration, the clean flue gas pipe connection of denitration has the denitration flue gas branch pipe, the denitration flue gas branch pipe links to each other with electromagnetic control valve, electromagnetic control valve passes through the mixed branch pipe of flue gas and communicates with sintering machine flue gas pipeline.

Compared with the prior art, the utility model has the beneficial effects that; according to the utility model, the heating furnace of the denitration device is used for heating the denitration device in advance, the denitration device is raised to the normal working temperature of about 200 ℃, meanwhile, denitration flue gas passes through the heat exchanger and then is introduced into the denitration flue gas branch pipe through the denitration clean flue gas pipeline, the electric regulating valve is automatically opened, the denitration flue gas enters the flue gas mixing branch pipe and then enters the sintering flue gas pipeline, and finally enters the SDA desulfurization device, and the internal temperature of the SDA desulfurization device is kept to be about 130 ℃. The system solves the problem that the desulfurization and denitrification effects are unstable in a period of time when the sintering machine starts to produce, and ensures that the flue gas emission reaches the standard.

Further, SDA desulphurization unit includes SDA desulfurizing tower, lime thick liquid storage tank and lime thick liquid pump, is provided with rotary atomizer, central gas distributor and top gas distributor in the SDA desulfurizing tower, and sintering machine flue gas pipeline communicates with central gas distributor, top gas distributor respectively, and rotary atomizer is connected to top gas distributor below, and rotary atomizer passes through the pipeline and links to each other with lime thick liquid pump, and lime thick liquid pump passes through the pipeline and links to each other with lime thick liquid storage tank.

Drawings

Fig. 1 is a schematic structural diagram of a sintering flue gas desulfurization and denitrification circulation system provided by an embodiment of the utility model;

FIG. 2 is a schematic structural diagram of an SDA desulfurization apparatus according to an embodiment of the present invention;

labeled as: 1. sintering machine; 2. flue gas pipelines of the sintering machine; 3. a flue gas mixing branch pipe; 4. an electromagnetic regulating valve; 5. an SDA desulfurization unit; 6. a dust remover; 7. heating furnace; 8. a chimney; 9. denitration flue gas branch pipes; 10. a denitration flue gas purification pipeline; 11. a heat exchanger; 12. a denitration device; 13. a lime slurry storage tank; 14. a lime slurry pump; 15. rotating the atomizer; 16. a central flue gas distributor; 17. a top flue gas distributor; 18. a central flue gas inlet duct; 19. a top flue gas inlet duct; 20. and (4) a flue gas outlet pipeline of the SDA desulfurization tower.

Detailed Description

The present invention will be described in detail with reference to the following embodiments in order to fully understand the objects, features and effects of the utility model, but the present invention is not limited thereto.

As shown in fig. 1 and fig. 2, the sintering flue gas denitration and desulfurization circulation system provided by the present invention comprises a sintering machine 1, a sintering machine flue gas pipeline 2, a flue gas mixing branch pipe 3, an electromagnetic regulating valve 4, an SDA desulfurization device 5, a dust remover 6, a heating furnace 7, a chimney 8, a denitration flue gas branch pipe 9, a denitration clean flue gas pipeline 10, a heat exchanger 11, and a denitration device 12. The heat exchanger 11 is a gas-gas heat exchanger, and is provided with a first gas inlet, a second gas inlet, a first outlet and a second outlet, and the high-temperature flue gas and the low-temperature flue gas respectively pass through a tube pass and a shell pass to preheat the low-temperature flue gas. The gas outlet of sintering machine 1 is connected with sintering machine flue gas pipeline 2's one end, and sintering machine flue gas pipeline 2's the other end is connected with SDA desulphurization unit 5's air inlet, and SDA desulphurization unit 5 passes through the pipeline and is connected with 6 access connections of dust remover, and 6 exports of dust remover are connected with 11 first air inlets of heat exchanger through the pipeline, and 11 first exports of heat exchanger are connected with 12 air inlets of denitrification facility. The denitration device 12 is an SCR reactor or an SNCR reactor.

The denitration device 12 is connected with the heating furnace 7, and the heating furnace 7 is used for promoting the flue gas temperature in the denitration device 12. The gas outlet of the denitration device 12 is connected with the second gas inlet of the heat exchanger 11, and the second outlet of the heat exchanger 11 is connected with the denitration clean flue gas pipeline 10. The clean flue gas pipeline 10 middle part of denitration is connected with denitration flue gas branch pipe 9, and denitration flue gas branch pipe 9 links to each other with 4 ports of electromagnetic control valve, and 3 one end intercommunications of another port of electromagnetic control valve and flue gas mixing branch pipe, and the 3 other ends of flue gas mixing branch pipe are connected with sintering machine flue gas pipeline 2 middle parts, and clean flue gas pipeline 10 tip of denitration is connected with chimney 8.

The SDA desulfurization device 5 comprises an SDA desulfurization tower, a central flue gas inlet pipeline 18, a top flue gas inlet pipeline 19, a lime slurry pump 14, a lime slurry storage tank 13 and the like, wherein the end part of the flue gas pipeline 2 of the sintering machine is simultaneously connected with the central flue gas inlet pipeline 18 and the top flue gas inlet pipeline 19, the central flue gas inlet pipeline 18 penetrates through the side wall of the SDA desulfurization tower to be connected with a central flue gas distributor 16, and the top flue gas inlet pipeline 19 is connected with a top flue gas distributor 17. Be provided with rotatory atomizer 15 in the SDA desulfurizing tower, central gas distributor 16 and top gas distributor 17, central gas distributor 16 is fixed at SDA desulfurizing tower inner chamber middle part, top gas distributor 17 is fixed on SDA desulfurizing tower inner chamber upper portion, top gas distributor below is connected with rotatory atomizer 15, rotatory atomizer 15 links to each other with lime thick liquid pump 14 through the pipeline, lime thick liquid pump 14 passes through the pipeline and links to each other with lime thick liquid storage tank 13, lime thick liquid storage tank 13 mixes lime and water together and forms the lime thick liquid, squeeze into rotatory atomizer 15 with the lime thick liquid through lime thick liquid pump 14, rotatory atomizer 15 spouts lime thick liquid atomizing SDA into the inside and sintering flue gas contact reaction of desulfurizing tower, the sintering flue gas after the reaction passes through SDA desulfurizing tower gas outlet pipe and gets into dust remover 6.

The using method comprises the following steps: in-situ flue gas treatment of a 384 square meter sintering machine, an SDA desulfurization device 5, a dust remover 6, a heat exchanger 11, a heating furnace 7 and an SCR denitration device 12 are adopted for sintering flue gas treatment, and the normal desulfurization temperature is required to be higher than 120 ℃, and the denitration temperature is higher than 180 ℃.

Before the sintering machine 1 starts to produce, the heating furnace 7 is opened to heat the denitration device 12, the temperature of the denitration device 12 is raised to 200 ℃ of normal working temperature, denitration flue gas enters the denitration flue gas branch pipe 9 through the denitration clean flue gas pipeline 10 after passing through the heat exchanger 11, meanwhile, the electromagnetic regulating valve 4 is automatically opened, the denitration flue gas enters the sintering flue gas pipeline 2 after entering the flue gas mixing branch pipe 3 and finally enters the SDA desulfurization device 5, and the internal temperature of the SDA desulfurization device 5 is kept at 130 ℃. At this time, the sintering machine 1 starts production, the generated sintering flue gas and the denitration flue gas form mixed flue gas in the sintering flue gas pipeline 2, the mixed flue gas enters the top flue gas inlet pipeline 19 and the central flue gas inlet pipeline 18 of the SDA desulfurization tower after being heated, and then enters the SDA desulfurization tower through the top flue gas distributor 17 and the central flue gas distributor 16, and the atomized lime slurry absorbs and reacts to obtain desulfurized flue gas, and the desulfurized flue gas enters the heat exchanger 11 through the dust remover 6 to exchange heat with the denitration flue gas, so that the temperature of the mixed flue gas is further increased, and finally the mixed flue gas enters the denitration system 12. When the production is stable and the sintering flue gas temperature reaches above 120 ℃, the electric regulating valve 4 is automatically and gradually closed, the operation of the sintering desulfurization and denitrification flue gas circulating system is finished, and the denitrated flue gas enters the atmosphere through the chimney 8.

The utility model has the beneficial effects that:

1. the pollutant emission is reduced, the emission of sulfur dioxide is reduced by about 15kg/h and the emission of nitrogen oxides is reduced by about 450kg/h, and sulfur trioxide and dioxin are ignored.

2. The yield of 468 tons of sinter is increased, and the profit of the self-produced sinter is increased by about 300 yuan compared with the purchasing of one ton of sinter, namely, the yield of 468X 300 is 140400 yuan.

3. The service life of the catalyst can be prolonged by 6 months, and the service cost of the catalyst for 6 months is 2865000 yuan according to the general service life of the catalyst being three years.

4. It is good for people around the world to live air quality.

Finally, it is noted that: the above-mentioned list is only the preferred embodiment of the present invention, and naturally those skilled in the art can make modifications and variations to the present invention, which should be considered as the protection scope of the present invention provided they are within the scope of the claims of the present invention and their equivalents.

Claims

1. A sintering flue gas desulfurization and denitrification circulating system comprises a sintering machine flue gas pipeline, an SDA desulfurization device, a dust remover, a heat exchanger, a denitrification device, a heating furnace, a denitrification clean flue gas pipeline, an electromagnetic regulating valve and a flue gas mixing branch pipe, wherein the heat exchanger comprises a first inlet, a second inlet, a first outlet and a second outlet; the denitration device is characterized in that one end of a flue gas pipeline of the sintering machine is connected with the sintering machine, the other end of the flue gas pipeline of the sintering machine is connected with the SDA desulfurization device, the SDA desulfurization device is connected with a dust remover, the dust remover is connected with a first inlet of a heat exchanger, a first outlet of the heat exchanger is connected with a denitration device, the denitration device is respectively connected with a heating furnace and a second inlet of the heat exchanger, a second outlet of the heat exchanger is communicated with a denitration clean flue gas pipeline, the denitration clean flue gas pipeline is connected with a denitration flue gas branch pipe, the denitration flue gas branch pipe is connected with an electromagnetic regulating valve, and the electromagnetic regulating valve is communicated with the flue gas pipeline of the sintering machine through a flue gas mixing branch pipe.

2. The sintering flue gas desulfurization and denitrification circulation system according to claim 1, wherein the SDA desulfurization device comprises an SDA desulfurization tower, a lime slurry storage tank and a lime slurry pump, a rotary atomizer, a central flue gas distributor and a top flue gas distributor are arranged in the SDA desulfurization tower, flue gas pipelines of the sintering machine are respectively communicated with the central flue gas distributor and the top flue gas distributor, the rotary atomizer is connected below the top flue gas distributor and is connected with the lime slurry pump through a pipeline, and the lime slurry pump is connected with the lime slurry storage tank through a pipeline.