CN109234483B - Blast furnace gas comprehensive treatment recovery device - Google Patents

Abstract

The invention discloses a blast furnace gas comprehensive treatment and recovery equipment, which includes a blast furnace top charging tank (1), a cyclone dust collector (4), an alkali spray washing tower (13) and a water eliminator (15). The blast furnace top charging tank The pressure-equalized gas outlet of (1) is connected to the inlet of the cyclone dust collector (4) through the gas delivery pipe, and the outlet of the cyclone dust collector (4) is connected to the pressure-equalized gas inlet of the alkali spray scrubber (13) through the pressure-equalized gas recovery pipe. connection, the diffused gas outlet of the blast furnace top charging tank (1) is connected to the diffused gas inlet of the alkali spray scrubber (13) through the diffused gas recovery pipe, and the water-containing gas outlet of the alkali spray scrubber (13) is connected to the gas removal pipe through the gas transmission pipeline. Inlet connection to water dispenser (15). The blast furnace gas comprehensive treatment and recovery equipment can not only realize the alkali spraying and acid removal treatment of the furnace top gas, the washing and dust removal treatment and recovery of the pressure-equalized gas, but also the dust removal and acid removal treatment of the large-dispersion gas.

Description

A comprehensive blast furnace gas treatment and recovery equipment

Technical field

The invention relates to the field of iron and steel smelting equipment, specifically a blast furnace gas comprehensive treatment and recovery equipment.

Background technique

The long-term gas emissions accompanying the normal production of blast furnace ironmaking include two parts: one part is the gas discharged from the material tank when the furnace top is charging, which is called equalization gas; the other part is the gas discharged from the furnace top due to the chemical reaction of the raw fuel in the blast furnace. It's called stove top gas. When the blast furnace interrupts production and stops air supply due to special reasons, the gas discharged from the top of the furnace is called large-dispersion gas.

The furnace top pressure-equalizing gas necessary for blast furnace production passes through the cyclone dust collector and silencer before being released into the atmosphere (about 300 times a day) before each charge. The pressure-equalizing gas contains a large amount of CO, CO _2. A toxic and combustible mixed gas with dust. The emission amount of pressure-equalized gas is 6-8Nm ³ /ton of iron, and the dust content exceeds 10g/Nm ^3. Our country produces about 700 million tons of molten iron every year, which is distributed through the top of the blast furnace. The amount of gas discharged into the atmosphere by pressure relief equipment is as high as 5.5 billion ^m3 /year. The unit price of blast furnace gas is calculated as 0.11 yuan/ ^Nm3 . The economic loss caused by this part of gas is about 600 million yuan/year, and the amount of dust emitted reaches 5.5 Thousands of tons/year. The pressure-equalized gas in the blast furnace ironmaking production process is directly discharged into the atmosphere, which not only causes atmospheric environmental pollution, but also wastes energy.

There are many technologies at home and abroad that can realize the recovery of pressure-equalized gas on the top of blast furnaces, and some have achieved good results. For example, Chinese patent CN102031321A, published on April 27, 2011, discloses a "pressure-equalized blast furnace top gas." Recycling methods and recycling devices”. However, these technologies all require the addition of special pressure-equalized gas dust removal equipment on the basis of the original blast furnace system to achieve dust removal of the pressure-equalized gas before recycling it. For most blast furnace systems that need to be modified on the original site, the floor space and additional equipment investment during the modification process are important issues that cannot be avoided.

During the production process, the blast furnace sometimes interrupts ironmaking production and arranges planned air breaks based on the needs of maintenance and accident handling. For example, to deal with damaged cooling staves, water needs to be pumped from the lowering surface; sometimes ironmaking is interrupted due to other reasons. Production, unplanned shutdown. When the wind is off, the blast furnace stops blowing and fuel injection. The original raw fuel in the blast furnace does not react fully. In addition, due to operations such as water extraction on the lowering surface, the composition of the gas discharged at this time is complex, including a large amount of water vapor, large amounts of water, etc. Granular dust, H ₂ , CH ₄ , CO, CO ₂ , N ₂ . The gas generated after the blast furnace is shut down does not meet the recycling requirements due to its high humidity, high temperature, complex composition, large dust content, large dust particle size, and explosiveness. For this part of large-dispersion gas, it is not suitable to use the bag dust collector in the blast furnace production process. There has been no good treatment method at home and abroad. The only way is to open the furnace top release valve for large-dispersion treatment, and remove the gas containing a large amount of dust pollutants. Large amounts of gas are discharged directly into the atmosphere, causing serious air pollution.

Many steel companies inject bituminous coal or anthracite to varying degrees in order to reduce the coke ratio. Some steel companies use imported raw materials ores that have been sprayed with seawater. Some steel companies use chlorine-containing additives (CaCl _2, etc.) to increase the strength of sinter. Since Due to the above reasons, the top gas produced by many domestic steel companies during the production process contains a large amount of acidic media (chloride ions and sulfate ions).

With the enlargement of blast furnaces and the increase in furnace top pressure, blast furnace gas purification methods have developed from wet to dry. The latest version of "Design Code for Blast Furnace Ironmaking Engineering" (GB50427-2015) clearly recommends that "blast furnace gas purification design should adopt dry methods." "French bag dust removal process", therefore, dry bag dust collectors are commonly used in China to complete the purification of furnace top gas. Dry dust removal cannot purify the acidic media in furnace top gas. These acidic media form strong acidic solutions when exposed to water, causing serious corrosion to gas pipelines. The "Design Code for Blast Furnace Ironmaking Engineering" (GB50427-2015) recommends that "when the content of corrosive substances such as chloride ions in the clean gas is high, an alkali spray tower should be installed before entering the gas pipe network of the whole plant to control the chloride ion content in the gas. facilities". In response to this situation, many domestic steel companies have adopted alkali spray towers as dechlorination devices for top gas while applying dry gas dust removal technology, such as Chinese patent CN201864738U, published on June 15, 2011. A "blast furnace gas alkali spray alkali dechlorination device".

Blast furnace production requires solving the corrosive problem of top gas in terms of technology, solving the problem of dust removal and recovery of pressure-equalized gas, and solving the problem of dust and acid removal of large-dispersion gas in terms of environmental protection. From the above analysis, it can be seen that the existing technology does not have a good treatment method for large-scale emission gas, and all gases are discharged directly into the air; for blast furnace top pressure-equalized gas, although the existing technology has provided many recovery methods, they all require additional dedicated equipment. The pressure-equalized gas dust removal equipment faces important problems such as floor space and investment in additional equipment during the transformation process. As an alkali spray tower for eliminating acidic media in gas, it only has the single function of spraying alkali to remove acid.

Contents of the invention

In order to complete the dust and acid removal of blast furnace gas. The invention provides a comprehensive blast furnace gas treatment and recovery equipment. The alkali spray scrubber in the blast furnace gas comprehensive treatment and recovery equipment has the functions of washing, dust removal, and alkali spraying and acid removal. There is no need to add additional pressure-equalizing gas dust removal equipment, and the blast furnace top is The coal gas and pressure-equalized gas are directly introduced into the alkali spray scrubber, which can not only realize the alkali spray and acid removal treatment of the top gas, the washing and dust removal treatment and recovery of the pressure-equalized gas, but also realize the dust removal and acid removal of large-dispersion gas.

The technical invention used by the present invention to solve the technical problems is: a comprehensive blast furnace gas treatment and recovery equipment, including a blast furnace top charging tank, a cyclone dust collector, an alkali spray washing tower and a water eliminator, and a pressure equalization of the blast furnace top charging tank The gas outlet is connected to the inlet of the cyclone dust collector through the gas transmission pipeline. The outlet of the cyclone dust collector is connected to the pressure-equalized gas inlet of the alkali spray scrubber through a pressure equalizing gas recovery pipe. The diffused gas outlet of the blast furnace top charging tank is recovered through diffused gas. The pipeline is connected to the diffuse gas inlet of the alkali spray scrubber, and the water-containing gas outlet of the alkali spray scrubber is connected to the inlet of the water eliminator through the gas transmission pipeline.

The alkali spray washing tower contains an air flow uniformity device, an alkali spray device, a demister, an upper spray device and a water removal device arranged in sequence from bottom to top. Along the vertical direction, the air flow uniformity device contains at least one layer of gas Grid, the alkali spray device contains at least one alkali spray layer.

The alkali spray washing tower is an upright cylindrical structure. An alkali spray layer contains a plurality of long spray guns and short spray guns evenly spaced along the circumference of the alkali spray washing tower. Each long spray gun and short spray gun are sprayed along the alkali spray The tower is arranged radially, and each long and short spray gun is equipped with a high-pressure atomizing nozzle.

The alkali spray device contains multiple alkali spray layers. Among the two adjacent alkali spray layers, the spray directions of the high-pressure atomizing nozzles in one alkali spray layer are all upward, and the spray directions of the high-pressure atomizing nozzles in the other alkali spray layer are all upward. The spray directions of the high-pressure atomizing nozzles in the alkali spray layer are all downward.

The alkali spray device contains four alkali spray layers, and the four alkali spray layers are the first alkali spray layer, the second alkali spray layer, and the third alkali spray layer in order from bottom to top. The alkali spray layer and the fourth alkali spray layer.

The spray directions of the high-pressure atomizing nozzles in the first alkali spray layer are all upward, the spray directions of the high-pressure atomization nozzles in the second alkali spray layer are all downward, and the third alkali spray layer is The spraying directions of the high-pressure atomizing nozzles in the spray layer are all upward, and the spraying directions of the high-pressure atomizing nozzles in the fourth alkali spray layer are all downward.

The upper spray device contains a plurality of nozzles that can spray water to the demister. The water removal device is a filler water removal device. The water removal device is located at the upper part of the alkali spray washing tower. The alkali spray washing tower also contains a dispersion gas outlet. The gas outlet and the water-containing gas outlet are both located at the top of the alkali spray scrubber, and a scrubber release valve is connected to the outside of the vented gas outlet.

There is a sewage outlet at the bottom of the alkali spray scrubber. There is a sewage treatment device below the sewage outlet. The alkali spray scrubber also contains a top gas inlet. A top gas recovery pipe is connected to the outside of the top gas inlet of the alkali spray scrubber. , the top gas recovery pipe is equipped with a top gas stop valve.

The pressure-equalizing gas recovery pipeline is equipped with a thermometer, a flow meter, a pressure gauge and a pressure-equalizing gas recovery valve. The outlet of the cyclone dust collector is connected to a parallel silencer and a primary pressure equalizing system. The gas delivery pipeline is connected to a series Nitrogen tank and secondary pressure equalization system, the outlet of the water eliminator is connected to the clean gas pipe network.

The beneficial effects of the present invention are:

1. It can complete the washing and dust removal of pressure-equalized gas, simplify the process of pressure-equalized gas recovery, and reduce the floor space.

2. It can complete the dust removal and acid removal treatment of large-dispersed gas and reduce air pollution.

3. It can complete the alkali spraying and acid removal treatment of the furnace top gas to reduce its corrosion on the gas pipeline.

4. The alkali spray scrubber has a simple structure, low construction cost and low maintenance cost.

5. The alkali spray scrubber has fewer movable parts, is less likely to malfunction, and has a high operating rate.

6. Before the pressure-equalized gas enters the alkali spray scrubber, the pressure, temperature and flow of the pressure-equalized gas are detected and fed back to the blast furnace central control system in time, which can optimize the operation of the blast furnace and promote smooth operation of the blast furnace.

Description of the drawings

The description and drawings that constitute a part of this application are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

Figure 1 is a schematic structural diagram of the blast furnace gas comprehensive treatment and recovery equipment according to the present invention.

Figure 2 is a schematic structural diagram of an alkali spray washing tower according to the present invention.

Figure 3 is a schematic structural diagram of an alkali spray layer.

1. Blast furnace top charging tank; 2. Secondary pressure equalizing valve; 3. Nitrogen tank; 4. Cyclone dust collector; 5. Primary pressure equalizing valve; 6. Silencer; 7. Pressure equalizing relief valve; 8. Thermometer; 9. Flow meter; 10. Pressure gauge; 11. Pressure equalizing gas recovery valve; 12. Washing tower relief valve; 13. Alkali spraying washing tower; 14. Stop valve of alkali spraying washing tower; 15. Drain eliminator; 16. Stop valve Return valve; 17. Clean gas pipe network; 18. Furnace top relief valve; 19. Large relief gas stop valve; 20. Furnace top gas stop valve; 21. Sewage treatment device; 22. Primary pressure equalizing system; 23. Secondary pressure equalizing system;

31. Water removal device; 32. Spray device; 33. Demister; 34. High-pressure atomizing nozzle; 35. Gas grille; 36. Alkaline spray layer; 37. Long spray gun; 38. Short spray gun.

Detailed ways

It should be noted that, as long as there is no conflict, the embodiments and features in the embodiments of this application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and embodiments.

A comprehensive blast furnace gas treatment and recovery equipment, including a blast furnace top charging tank 1, a cyclone dust collector 4, an alkali spray scrubber 13 and a water eliminator 15. The pressure-equalized gas outlet of the blast furnace top charging tank 1 communicates with the cyclone through a gas delivery pipe The inlet of the dust collector 4 is connected, the outlet of the cyclone dust collector 4 is connected with the pressure-equalized gas inlet of the alkali spray scrubber 13 through the pressure equalizing gas recovery pipe, and the diffused gas outlet of the blast furnace top charging tank 1 is connected with the alkali sprayed gas outlet through the diffused gas recovery pipe. The diffuse gas inlet of the scrubber 13 is connected, and the water-containing gas outlet of the alkali spray scrubber 13 is connected to the inlet of the water eliminator 15 through a gas transmission pipeline, as shown in Figure 1 .

In this embodiment, the alkali spray washing tower 13 contains an air flow uniformity device, an alkali spray device, a demister 33, an upper spray device 32 and a water removal device 31 arranged in sequence from bottom to top. Along the vertical direction, The air flow uniformity device includes at least one layer of gas grid 35, and the alkali spray device includes at least one alkali spray layer 36, as shown in Figure 2.

In this embodiment, the pressure-equalized gas inlet and the diffused gas inlet of the alkali-sprayed scrubber 13 are located at the lower part of the alkali-sprayed scrubber 13, and the air flow uniformity device is located above the pressure-equalized gas inlet and the diffused gas inlet. The uniform device contains three layers of gas grilles 35, and the adjacent two layers of gas grilles 35 are staggered by a set angle, so that the blast furnace gas entering the tower is evenly distributed on the cross section of the entire tower.

In this embodiment, the alkali spray washing tower 13 has an upright cylindrical structure, and the alkali spray layer 36 contains a plurality of long spray guns 37 and short spray guns 38 evenly spaced along the circumferential direction of the alkali spray washing tower 13. The long spray guns 37 intersects at the centerline position of the alkali spray scrubber 13. Both the long spray gun 37 and the short spray gun 38 are columnar structures. The length of the long spray gun 37 is greater than the length of the short spray gun 38. Both the long spray gun 37 and the short spray gun 38 are along the alkali spray scrubber. 13 is arranged in the radial direction, that is, the length direction of the long spray gun 37 and the length direction of the short spray gun 38 are both arranged along the radial direction of the alkali spray washing tower 13. Both the long spray gun 37 and the short spray gun 38 are provided with multiple high-pressure atomizing nozzles 34. ,As shown in Figure 3.

In this embodiment, the alkali spray device includes a plurality of alkali spray layers 36 spaced apart in the vertical direction. Among the two adjacent alkali spray layers 36, one alkali spray layer The spraying directions of the high-pressure atomizing nozzles 34 in 36 are all upward, and the spraying directions of the high-pressure atomizing nozzles 34 of the other alkali spray layer 36 are all downward. For example, the alkali spray device includes four alkali spray layers 36. As shown in Figure 2, the four alkali spray layers 36 are the first alkali spray layer, the first alkali spray layer and the first alkali spray layer 36 in order from bottom to top. The second alkali spray layer, the third alkali spray layer and the fourth alkali spray layer.

The spray directions of the high-pressure atomizing nozzles 34 in the first alkali spray layer are all upward, the spray directions of the high-pressure atomization nozzles 34 in the second alkali spray layer are all downward, and the spray directions of the third alkali spray layer are all upward. The spraying directions of the high-pressure atomizing nozzles 34 in the spray layer are all upward, and the spraying directions of the high-pressure atomizing nozzles 34 in the fourth alkali spray layer are all downward. The bottom of the alkali spray washing tower 13 is provided with a sewage outlet, and there is a sewage treatment device 21 below the sewage outlet. The dusty sewage generated after the blast furnace gas comprehensive treatment and recovery equipment processes the gas is processed by the sewage treatment device 21 to obtain sludge and recyclable reclaimed water.

According to process requirements, multiple alkali spray layers 36 and their accompanying high-pressure atomization nozzles 34 are arranged at different heights. After the alkali liquid is sprayed from the high-pressure atomizing nozzle 34, it forms an atomized state inside the alkali spray washing tower 13, and the atomized alkali liquid evenly fills the internal space of the alkali spray washing tower 13. The high-pressure atomization nozzle 34 sprays the alkali liquid in a high-pressure atomization state to achieve dechlorination of the gas.

The acidic dusty blast furnace gas enters the alkali spray scrubber 13 from the gas inlet on the lower side of the alkali spray scrubber 13 (including the pressure equalizing gas inlet, the diffuse gas inlet and the furnace top gas inlet). Under the action of the atomized alkali liquid, the process is completed. Acid removal and dust removal treatment:

1. Alkali spraying and acid removal treatment: The atomized alkali liquid filling the internal space of the alkali spraying scrubber 13 fully reacts with the acidic medium in the gas to eliminate the corrosiveness of the gas.

2. Washing and dust removal treatment: Due to the inertial collision, interception and agglomeration between atomized alkali liquid and gas dust, larger particles of dust settle by gravity with atomized washing, are discharged together with the washing liquid, and enter the alkali spray washing tower 13. Sewage treatment device 21 outside the sewage outlet at the bottom. The dusty sewage can be recycled after being treated by the sewage treatment device 21 at the bottom of the alkali spray scrubber 13 .

In this embodiment, the upper spray device 32 includes a plurality of nozzles capable of spraying water to the demister 33 . The water removal device 31 is a filler water removal device. The water removal device 31 is located at the upper part of the alkali spray washing tower 13 . The demister 33 can be a wire mesh demister (or other types of high-efficiency demisters such as a folding plate demister), and the demister 33 is arranged in the space above the high-pressure atomizing nozzle 34 . The smaller particles of dust and the atomized alkali liquid form mist. The gas with the mist rises at a certain speed through the demister 33. The demister 33 completes the treatment of the smaller dust particles in the gas to obtain water-containing purified air. gas. An upper spray device 32 is provided above the demister 33, and high-pressure water is regularly used to spray and flush the demister 33 through the upper spray device 32 to prevent the demister 33 from being clogged after long-term use. The acidic dust-containing blast furnace gas passes through the atomized alkali liquid sprayed from the high-pressure atomizing nozzle 34 and the action of the demister 33 to obtain gas with a relatively large moisture content.

In this embodiment, the top of the alkali spray scrubber 13 is provided with two gas outlets. The two gas outlets are a water-containing gas outlet and a release gas outlet respectively. The release gas outlet is connected to a scrubbing tower release valve 12. Outside the water-containing gas outlet, there are alkali spray scrubber stop valve 14, water eliminator 15, check valve 16 and clean gas pipe network 17, as shown in Figure 1.

A water removal device 31 (packing water removal device) is provided above the upper spray device 32 close to the top outlet of the alkali spray washing tower 13. The internal filler of the filler water removal device can be made of aluminum alloy rosette filler (or stainless steel rosette filler or other types of filler). When the water-containing gas passes through the water removal device 31, the small water droplets in the gas gather into large water droplets under the action of the filler, and preliminary water removal is achieved under the action of gravity.

The water eliminator 15 can be a baffle type water eliminator (or other types of high-efficiency water eliminators such as a cyclone type water eliminator). The water-containing gas after preliminary water removal is discharged from the water-containing gas outlet at the top of the alkali spray scrubber 13, and enters the water eliminator 15 provided outside the top of the alkali spray scrubber 13 to complete the water removal treatment of the water-containing gas, and finally obtain a qualified gas that meets the user's requirements. The gas enters the clean gas pipe network 17 through the clean gas check valve 16 for users to use.

The top outlet of the alkali spray washing tower 13 is provided with a washing tower relief valve 12. The washing tower relief valve 12 has the functions of a stop valve and a safety valve at the same time: when the internal pressure of the alkali spraying washing tower 13 is normal, the washing tower relief valve 12 is in a closed state. ; When the pressure exceeds the set value, the washing tower relief valve 12 automatically opens to reduce the internal pressure.

Under normal production conditions of the blast furnace, close the large release gas stop valve 19 of the large release gas pipeline and the alkali spray scrubber release valve 12 at the top outlet of the alkali spray scrubber, and open the top gas stop valve 20 of the furnace top gas pipeline and the pressure-equalizing gas Pipe recovery valve 11, open the stop valve 14 of the alkali spray scrubber at the top outlet of the alkali spray scrubber and the check valve 16 before the clean gas enters the pipeline network.

After the blast furnace charging system enters the charging process into the blast furnace top charging tank 1, the equalized pressure gas is discharged from the blast furnace top charging tank 1 and enters the cyclone dust collector 4 for rough dust removal. The gas after rough dust removal enters the equalizing pressure gas recovery pipe. A thermometer 8, a flow meter 9, and a pressure gauge 10 that measure the temperature, flow rate, and pressure of the equalized gas are installed on the pressure-equalized gas recovery pipeline. Their detection values are fed back to the blast furnace central control system in a timely manner to optimize the operation of the blast furnace and promote smooth operation of the blast furnace.

The pressure-equalized gas passes through the pressure-equalized gas recovery valve 11 and is finally led to the alkali spray scrubber 13 with acid removal and dust removal functions; the furnace top gas enters the alkali spray scrubber 13 through the furnace top gas stop valve 20. According to the process requirements, the pressure equalizing gas recovery valve 11 or the furnace top gas stop valve 20 can be opened respectively to process the furnace top gas and the pressure equalizing gas respectively; the pressure equalizing gas recovery valve 11 or the furnace top gas stop valve 20 can also be opened at the same time. Handle top gas and pressure equalization gas.

In this embodiment, the alkali spray scrubber 13 also contains a top gas inlet, which is located at the lower part of the alkali spray scrubber 13. A top gas recovery pipe is connected to the outside of the top gas inlet of the alkali spray scrubber 13. , the top gas recovery pipe is provided with a top gas stop valve 20. The outlet of the cyclone dust collector 4 is connected to a parallel muffler 6 and a primary pressure equalizing system 22, and the gas transportation pipeline is connected to a series connected nitrogen tank 3 and a secondary pressure equalizing system 23, as shown in Figure 1.

In this embodiment, the diameter and height of the alkali spray scrubber 13 are determined based on the average flow rate of blast furnace gas in the tower. The blast furnace gas comprehensive treatment device proposed by the present invention automatically adjusts the water spray volume of the high-pressure atomizing nozzle 34 by detecting the gas pressure, flow rate and flow rate at the blast furnace gas inlet, and improves the acidic dust-containing gas and atomized alkali inside the alkali spray washing tower 13. Neutralization reaction of liquid and dust removal effect.

The alkali spray scrubber 13 of the present invention has a high dust removal efficiency and can remove dust with a particle size of 0.1-20 microns, and the dust content of the treated gas is less than 5 mg/m ³ . After the water-containing clean gas is processed by the filler water removal device 31 and the water eliminator 15, the mechanical water content is less than 7g/m ³ . The top gas and pressure-equalized gas processed by the blast furnace gas comprehensive treatment and recovery equipment proposed by the present invention meet the recovery requirements.

The gas grille 35, demister 33, upper spray device 32 and water removal device 31 described in the present invention can all adopt existing commercially available products. Therefore, the alkali spray scrubber 13 proposed by the present invention has the advantages of simplicity, low cost, low maintenance cost, few movable parts, less prone to failure, and high operating rate. It can reduce air pollution, achieve energy conservation, emission reduction, and resource recycling.

The working process of the blast furnace gas comprehensive treatment and recovery equipment according to the present invention is introduced below.

After the blast furnace charging system enters the charging process into the tank, open the pressure equalizing gas recovery valve 11 and the check valve 16 of the clean gas pipe network. The pressure equalizing gas is discharged from the blast furnace top charging tank 1 and then enters the cyclone dust collector 4 Carry out rough dust removal, and the gas after rough dust removal enters the pressure-equalized gas recovery pipe. A thermometer 8, a flow meter 9, and a pressure gauge 10 that measure the temperature, flow rate, and pressure of the equalized gas are installed on the pressure-equalized gas recovery pipeline. Their detection values are fed back to the blast furnace central control system in a timely manner to optimize the operation of the blast furnace and promote smooth operation of the blast furnace.

The pressure-equalized gas passes through the pressure-equalized gas recovery valve 11 and is finally led to the alkali spray scrubber 13 with the functions of acid removal and dust removal; the furnace top gas enters the alkali spray scrubber 13 through the furnace top gas cut-off valve 20. According to the process requirements, the pressure equalizing gas recovery valve 11 or the furnace top gas stop valve 20 can be opened respectively to process the furnace top gas and the pressure equalizing gas respectively; the pressure equalizing gas recovery valve 11 or the furnace top gas stop valve 20 can also be opened at the same time. Handle top gas and pressure equalization gas.

When the blast furnace is shut down, close the pressure equalizing gas recovery valve 11 and the top gas stop valve 20, close the scrubber stop valve 14 at the top outlet of the alkali spray scrubber 13 and the check valve 16 before the clean gas enters the pipe network, and open the large release gas The large release gas cut-off valve 19 of the pipeline and the scrubber release valve 12 at the top outlet of the alkali spray scrubber.

The large-dispersed coal gas is processed by the alkali spray scrubber 13 to eliminate acidic media and dust to meet the emission requirements, and is discharged into the air through the scrubber discharge valve 12.

The present invention can realize the comprehensive treatment of three types of blast furnace gas by using the alkali spray scrubber 13: during blast furnace production, it can not only realize the alkali spraying and acid removal treatment of the top gas to eliminate its corrosiveness, but also can complete the equalization of pressure gas. Washing, dust removal and recovery functions; when the blast furnace is shut down, it can complete the dust removal and acid removal of large-dispersion gas, and discharge it into the air after meeting the emission requirements.

The blast furnace gas comprehensive treatment and recovery equipment of the present invention can reduce air pollution, achieve energy conservation, emission reduction and resource recycling.

The above are only specific embodiments of the present invention and cannot be used to limit the scope of the invention. Therefore, the replacement of equivalent components, or equivalent changes and modifications made according to the patent protection scope of the present invention, should still be covered by this patent. category. In addition, the technical features in the present invention can be freely combined with each other, between technical features and technical inventions, and between technical inventions and technical inventions.

Claims (4)

1. The blast furnace gas comprehensive treatment recovery device is characterized by comprising a blast furnace top charging tank (1), a cyclone dust collector (4), an alkali spraying washing tower (13) and a dehydrator (15), wherein a pressure equalizing gas outlet of the blast furnace top charging tank (1) is connected with an inlet of the cyclone dust collector (4) through a gas conveying pipeline, an outlet of the cyclone dust collector (4) is connected with a pressure equalizing gas inlet of the alkali spraying washing tower (13) through a pressure equalizing gas recovery pipeline, a bleeding gas outlet of the blast furnace top charging tank (1) is connected with a bleeding gas inlet of the alkali spraying washing tower (13) through a bleeding gas recovery pipeline, and a water-containing gas outlet of the alkali spraying washing tower (13) is connected with an inlet of the dehydrator (15) through a gas conveying pipeline;

the alkali spraying washing tower (13) is internally provided with an air flow homogenizing device, an alkali liquor spraying device, a foam remover (33), an upper spraying device (32) and a water removing device (31) which are sequentially arranged from bottom to top, wherein the air flow homogenizing device comprises three layers of air grids (35) along the vertical direction, and two adjacent layers of air grids (35) are staggered at a set angle;

the alkali spraying washing tower (13) is of an upright cylindrical structure, one alkali spraying layer (36) comprises a plurality of long spray guns (37) and short spray guns (38) which are uniformly arranged at intervals along the circumferential direction of the alkali spraying washing tower (13), each long spray gun (37) and each short spray gun (38) are arranged along the radial direction of the alkali spraying washing tower (13), and each long spray gun (37) and each short spray gun (38) are provided with a high-pressure atomizing nozzle (34);

the alkali liquor spraying device comprises four alkali liquor spraying layers (36), wherein the four alkali liquor spraying layers (36) are a first alkali liquor spraying layer, a second alkali liquor spraying layer, a third alkali liquor spraying layer and a fourth alkali liquor spraying layer in sequence from bottom to top;

the spraying directions of the high-pressure atomizing nozzles (34) in the first alkali liquor spraying layer are all upward, the spraying directions of the high-pressure atomizing nozzles (34) in the second alkali liquor spraying layer are all downward, the spraying directions of the high-pressure atomizing nozzles (34) in the third alkali liquor spraying layer are all upward, and the spraying directions of the high-pressure atomizing nozzles (34) in the fourth alkali liquor spraying layer are all downward.

2. The blast furnace gas comprehensive treatment and recovery device according to claim 1, wherein the upper spraying device (32) comprises a plurality of nozzles capable of spraying water flow to the demister (33), the dewatering device (31) is a filler dewatering device, the dewatering device (31) is positioned at the upper part of the alkali spraying washing tower (13), the alkali spraying washing tower (13) further comprises a diffused gas outlet, the diffused gas outlet and the water-containing gas outlet are both positioned at the top of the alkali spraying washing tower (13), and a washing tower diffused valve (12) is connected outside the diffused gas outlet.

3. Blast furnace gas comprehensive treatment and recovery equipment according to claim 1, characterized in that the bottom of the alkali spraying washing tower (13) is provided with a sewage drain, a sewage treatment device (21) is arranged below the outside of the sewage drain, the alkali spraying washing tower (13) also comprises a top gas inlet, a top gas recovery pipeline is connected to the outside of the top gas inlet of the alkali spraying washing tower (13), and a top gas stop valve (20) is arranged on the top gas recovery pipeline.

4. The blast furnace gas comprehensive treatment and recovery device according to claim 1, wherein a thermometer (8), a flowmeter (9), a pressure gauge (10) and a pressure equalizing gas recovery valve (11) are arranged on the pressure equalizing gas recovery pipeline, an outlet of the cyclone dust collector (4) is connected with a silencer (6) and a primary pressure equalizing system (22) which are connected in parallel, the gas conveying pipeline is connected with a nitrogen tank (3) and a secondary pressure equalizing system (23) which are connected in series, and an outlet of the water remover (15) is connected with a clean gas pipe network (17).