Sintering flue gas comprehensive utilization power generation and pollutant collaborative treatment system

Abstract

The utility model relates to a sintering flue gas comprehensive utilization power generation and pollutant collaborative treatment system. Comprising a boiler, a dust remover and a desulfurization mechanism, the dust remover is connected with a flue gas outlet end of the boiler, the desulfurization mechanism is connected with the dust remover, the sintering flue gas pipeline is connected with a flue gas inlet of an air pre-heater of the boiler, and a flue gas outlet of the air pre-heater is connected with a gas injection gun of a hearth of the boiler. The sintering flue gas is subjected to heat exchange and temperature rise through the air pre-heater of the boiler and then is conveyed into the boiler hearth to serve as combustion-supporting air, the combustion efficiency of the sintering flue gas can be improved, CO heat energy in the sintering flue gas is fully utilized, and CO emission is reduced; and the flue gas generated by the boiler is subjected to denitration and desulfurization treatment, so that the content of pollutants in the flue gas can be effectively reduced, and the ultra-low emission requirement is met.

Description

Technical Field

[0001] The utility model relates to the technical field of steel sintering fume treatment, in particular to a sintering fume comprehensive utilization power generation and pollutant coordinated treatment system. Background Art

[0002] The main air pollutants contained in sintering flue gas are SO 2 、NO x The treatment and purification of sintering flue gas is the key to energy conservation and emission reduction of atmospheric pollutants in the metallurgical industry. At present, the technology of flue gas desulfurization and denitrification at the head of sintering machine has been maturely developed, and the ultra-low emission transformation of the steel industry has been basically completed.

[0003] Sintering flue gas contains a large amount of carbon monoxide, accounting for about 1% to 2% of the flue gas, with a concentration of about 5000 to 15000 mg / m 3 As the country's requirements for CO emissions increase, CO will be included in the management and control of flue gas pollutants. In recent years, many parts of the country have also issued management requirements for CO emissions in the steel industry.

[0004] At present, most sintering flue gas is not reused, but directly discharged after traditional flue gas desulfurization and denitrification at the tail, which wastes a large amount of combustible substances in the flue gas and fails to achieve CO emission reduction control, resulting in waste of CO thermal energy and fan energy consumption, and causing certain impacts on the environment. Therefore, how to comprehensively utilize sintering flue gas and coordinately control SO contained in the flue gas is a key issue. 2 、NO x The removal of most pollutants, including particulate matter, heavy metals, CO and dioxins, while producing certain economic benefits is an urgent problem to be solved by technicians in this field. Utility Model Content

[0005] In order to solve the above problems, the utility model provides a sintering flue gas comprehensive utilization power generation and pollutant coordinated treatment system, including a boiler, a dust collector and a desulfurization mechanism, the dust collector is connected to the flue gas outlet end of the boiler, the desulfurization mechanism is connected to the dust collector, and also includes a sintering flue gas pipeline, the sintering flue gas pipeline is connected to the flue gas inlet of the air preheater of the boiler, and the flue gas outlet of the air preheater is connected to the jet gun of the furnace of the boiler.

[0006] Furthermore, it also includes a desulfurizer bin, which is connected to the desulfurization lance of the furnace through a desulfurization pipeline.

[0007] Furthermore, it also includes a pulverized coal bin, which is connected to the coal injection gun of the furnace through a pulverized coal pipeline.

[0008] Furthermore, a first fan is provided on the sintering fume duct, and the air jet gun is provided at the bottom of the furnace.

[0009] Furthermore, the boiler also includes a separator and a tail flue, the separator is connected to the flue gas outlet of the furnace, the tail flue is connected to the flue gas outlet of the separator, an upper economizer, an SCR reactor, and a lower economizer are sequentially arranged in the tail flue along the flue gas flow direction, and the air preheater is arranged at the end of the tail flue.

[0010] Furthermore, a denitrification spray gun is provided on the separator, and the denitrification spray gun is connected to a denitrification agent bin via a pipeline.

[0011] Furthermore, a solid material outlet is provided at the bottom of the separator, and the solid material outlet is connected to the furnace through a solid material pipeline.

[0012] Furthermore, the desulfurization mechanism comprises an activated coke desulfurization device, and an outlet end of the activated coke desulfurization device is connected to a chimney.

[0013] Furthermore, the desulfurization mechanism also includes an activated coke regeneration device and an acid-making unit, the discharge end of the activated coke regeneration device is connected to the feed end of the activated coke desulfurization device through a first activated coke chain bucket conveyor, and the discharge end of the activated coke desulfurization device is connected to the feed end of the activated coke regeneration device through a second activated coke chain bucket conveyor; the acid-making unit is connected to the activated coke regeneration device.

[0014] Furthermore, the dust collector is a bag dust collector, and a second fan is provided on the pipeline between the dust collector and the desulfurization mechanism.

[0015] Due to the adoption of the above technical solution, the utility model has the following beneficial effects compared with the prior art:

[0016] 1) In the utility model, the sintering flue gas is heated by the air preheater of the boiler and then sent to the boiler furnace as combustion-supporting air, which can improve the combustion efficiency of the sintering flue gas, make full use of the CO heat energy in the sintering flue gas, recycle the sintering flue gas and generate certain economic benefits, and reduce CO emissions; and the flue gas generated by the boiler is treated with denitrification and desulfurization, which can effectively reduce SO in the flue gas. 2 、NO x , particulate matter, heavy metals, CO and dioxins, meeting ultra-low emission requirements.

[0017] 2) In the utility model, the desulfurization efficiency can be improved by spraying the desulfurizer in the furnace and the desulfurization mechanism; and the activated coke in the activated coke desulfurization device can be regenerated to regenerate the precipitated SO 2 It can be used to prepare sulfuric acid and remove SO in flue gas. 2 Carry out comprehensive utilization to improve economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 This is a schematic diagram of the sintering flue gas comprehensive utilization power generation and pollutant coordinated treatment system provided by the utility model.

[0020] 10-boiler; 11-furnace; 12-separator; 121-solid material pipeline; 13-tail flue; 14-upper economizer; 15-SCR reactor; 16-lower economizer; 17-air preheater; 18-denitrification spray gun; 20-dust collector; 30-desulfurization mechanism; 31-activated coke desulfurization device; 32-activated coke regeneration device; 33-acid production unit; 34-first activated coke chain bucket machine; 35-second activated coke chain bucket machine; 40-sintering flue gas pipeline; 41-first fan; 50-pulverized coal bin; 51-pulverized coal pipeline; 60-denitrification agent bin; 61-ammonia storage bin; 62-desalted water storage bin; 63-denitrification pipeline; 70-desulfurization agent bin; 71-desulfurization pipeline; 80-second fan; 90-chimney. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of them. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model. In the drawings, the size and relative size of some parts may be enlarged for clarity.

[0022] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connection" and "connected" should be interpreted in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] In the description of the present invention, terms such as "upper", "lower", "left", "right", "front", "back", "center", "horizontal", "vertical", "top", "bottom", "inside" and "outside" and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of description and simplification of operation, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0024] In addition, in the description of the present invention, the terms "first" and "second" are only used to distinguish in the description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. In addition, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0025] As the instruction manual Figure 1 As shown, the utility model provides a sintering flue gas comprehensive utilization power generation and pollutant coordinated treatment system, including a boiler 10, a dust collector 20 and a desulfurization mechanism 30, the dust collector 20 is connected to the flue gas outlet end of the boiler 10, and is used to remove dust from the flue gas coming out of the boiler 10, the desulfurization mechanism 30 is connected to the dust collector 20, and is used to desulfurize the flue gas after preliminary dust removal, and also includes a sintering flue gas duct 40, the sintering flue gas duct 40 is connected to the flue gas inlet of the air preheater 17 of the boiler 10, and the flue gas outlet of the air preheater 17 is connected to the jet gun of the furnace 11 of the boiler 10.

[0026] Preferably, the boiler can be an integrated boiler or a separate boiler and can be configured according to actual needs. In the present application, the boiler is preferably a split boiler. The boiler 10 includes a furnace 11, a separator 12 and a tail flue 13 connected in sequence. An upper economizer 14, an SCR reactor 15, a lower economizer 16 and an air preheater 17 are sequentially arranged in the tail flue 13 along the flue gas flow direction. The sintering flue gas duct 40 is sprayed into the furnace 11 through a jet gun after heat exchange with the air preheater 17.

[0027] Specifically, the sintering flue gas contains combustible gas CO. On the one hand, in order to improve the utilization rate of CO thermal energy in the sintering flue gas, and on the other hand, in order to purify the sintering flue gas to reduce pollution to the environment, save energy and reduce emissions, the sintering flue gas from the sintering machine head is drawn in, and the sintering flue gas duct 40 is connected to the air preheater 17 and extends into the furnace 11. The sintering flue gas in the sintering flue gas duct 40 exchanges heat with the air preheater 17, so that the temperature in the sintering flue gas is increased. There is no need for preheating, and the waste heat of the flue gas can be used to heat the sintering flue gas. The sintering flue gas heated by the air preheater 17 is sent to the furnace 11 and burned as combustion-supporting air, so that the CO thermal energy in the sintering flue gas can be fully utilized. The flue gas generated is desulfurized and denitrated after the waste heat is recovered through the tail flue 13 to meet the emission standards. The flue gas generated by the furnace 11 enters the tail flue 13, passes through the upper economizer 14, the lower economizer 16 and the air preheater 17, so as to realize the heat exchange of the flue gas. The generated steam is sent to generate electricity. The tail flue 13 is also connected to a steam turbine. The generated steam is sent to the steam turbine to drive the steam turbine to rotate, thereby enabling the generator connected to the steam turbine to generate electricity, thereby realizing the combustion of sintering flue gas for power generation.

[0028] The optimized implementation mode also includes a pulverized coal bin 50, which is connected to the furnace 11 through a pulverized coal pipeline 51; preferably, pulverized coal is stored in the pulverized coal bin 50, and the pulverized coal is delivered to the furnace 11 as needed to be burned in combination with the sintering flue gas, thereby making full use of the combustible substances in the sintering flue gas to achieve sintering flue gas coal-fired power generation.

[0029] Specifically, in order to control the amount of pulverized coal, a weighable screw conveyor may be provided on the pulverized coal pipeline 51 to weigh the pulverized coal, provide a quantitative supply of the pulverized coal, and save the amount of pulverized coal.

[0030] Preferably, in order to prevent coal powder from agglomerating, a grinder may be provided at the discharge end of the coal powder bin 50 to grind agglomerated coal powder.

[0031] In an optimized implementation manner, a first fan 41 is further provided on the sintering fume duct 40 , and the gas injection gun is provided at the bottom of the furnace 11 .

[0032] In an optimized implementation mode, a denitrification spray gun 18 is provided on the separator 12, and the denitrification spray gun 18 is connected to a denitrification agent bin 60 through a pipeline; in an optimized implementation mode, the denitrification agent bin 60 includes an ammonia water storage bin 61 and a desalted water storage bin 62, and the ammonia water storage bin 61 and the desalted water storage bin 62 are respectively connected to a denitrification pipeline 63 through respective branch pipes for conveying ammonia water and desalted water, mixing ammonia water with desalted water, diluting the ammonia water, and feeding the ammonia water into the denitrification spray gun 18, spraying the ammonia water into the separator 12, and utilizing the high-temperature flue gas of the boiler to realize SNCR denitrification in the furnace; preferably, the denitrification spray gun 18 is arranged close to the flue gas inlet end of the separator 12.

[0033] Preferably, the flue gas generated in the furnace 11 is mixed with ammonia water in the separator 12 to perform SNCR denitration in the furnace. When the flue gas after denitration passes through the tail flue 13, it is further denitrated in the SCR reactor 15. Excess ammonia enters the tail flue 13 with the flue gas. Combined with SCR denitration, NO in the flue gas at the boiler outlet can be controlled. x Concentration ≤50mg / Nm 3 .

[0034] Preferably, the separator 12 is a cyclone separator, which can perform gas-solid separation. The flue gas in the furnace 11 enters the separator 12, and through the action of the cyclone separator, the particulate matter carried in the flue gas can be precipitated in the separator 12 and recovered to the furnace 11 through the solid material pipe 121 at the bottom of the separator 12; preferably, the bottom of the separator 12 is conical, and the solid material pipe 121 is provided with a U-shaped bend, so that the material in the solid material pipe 121 can be smoothly transported to the furnace for reuse.

[0035] The optimized implementation mode further includes a desulfurizer bin 70, which is connected to the desulfurization spray gun of the furnace 11 through a desulfurization pipeline 71; preferably, the desulfurizer can be limestone powder, and the desulfurizer bin 70 is a limestone powder bin, which delivers limestone to the furnace 11 to achieve desulfurization in the boiler furnace, and can control the SO in the flue gas at the boiler outlet. 2 Concentration ≤1500mg / Nm 3 After the flue gas is desulfurized in the furnace, the flue gas discharged from the boiler is further desulfurized in the desulfurization mechanism 30, which can effectively remove sulfur elements in the flue gas.

[0036] In an optimized implementation mode, the dust collector 20 is a bag dust collector, and a second fan 80 is provided on the pipeline between the dust collector 20 and the desulfurization mechanism 30. The second fan 80 generates negative pressure, so that the flue gas enters the desulfurization mechanism 30 for desulfurization treatment after being dust-removed by the dust collector 20.

[0037] In an optimized implementation mode, the desulfurization mechanism 30 includes an activated coke desulfurization device 31, and the outlet end of the activated coke desulfurization device 31 is connected to a chimney 90; after the flue gas is desulfurized in the furnace, it enters the activated coke desulfurization device 31 for desulfurization, and is discharged through the chimney 90 after meeting the standards. The SO in the flue gas at the outlet of the chimney 90 is 2 Concentration ≤35mg / Nm 3 , particle concentration ≤10mg / Nm 3 .

[0038] In an optimized implementation mode, the desulfurization mechanism 30 further includes an activated coke regeneration device 32 and an acid-making unit 33. The discharge end of the activated coke regeneration device 32 is connected to the feed end of the activated coke desulfurization device 31 through a first activated coke chain bucket 34, and the discharge end of the activated coke desulfurization device 31 is connected to the feed end of the activated coke regeneration device 31 through a second activated coke chain bucket 35. When the activated coke has been running for a period of time, its activity decreases, and the deactivated activated coke is sent to the activated coke regeneration device 32 through the second activated coke chain bucket 35 for activated coke regeneration. The regenerated activated coke is sent to the activated coke desulfurization device 31 through the first activated coke chain bucket 34 for continuous recycling, thereby ensuring the normal operation of the activated coke desulfurization device 31. During the regeneration process of the activated coke in the activated coke regeneration device 32, a high concentration of SO 2 The acid-making unit 33 is connected to the activated coke regeneration device 32 to convert SO 2 Gas to prepare concentrated sulfuric acid, SO in flue gas 2 Comprehensive utilization has been achieved.

[0039] Meanwhile, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0040] Those skilled in the art will appreciate that the present invention can be implemented in many other specific forms without departing from the spirit and scope of the present invention. Although the embodiments of the present invention have been described, it should be understood that the present invention should not be limited to this embodiment, and those skilled in the art can make changes and modifications within the spirit and scope of the present invention as defined by the attached claims.

Claims

1. A sintering flue gas comprehensive utilization power generation and pollutant coordinated treatment system, comprising a boiler, a dust collector and a desulfurization mechanism, wherein the dust collector is connected to the flue gas outlet of the boiler, and the desulfurization mechanism is connected to the dust collector, characterized in that: It also includes a sintering flue gas pipeline, which is connected to the flue gas inlet of the air preheater of the boiler, and the flue gas outlet of the air preheater is connected to the gas injection gun of the furnace of the boiler.

2. The sintering flue gas comprehensive utilization power generation and pollutant coordinated treatment system according to claim 1 is characterized in that: It also includes a desulfurizer bin, which is connected to the desulfurization spray gun of the furnace through a desulfurization pipeline.

3. The sintering flue gas comprehensive utilization power generation and pollutant coordinated treatment system according to claim 1 is characterized in that: It also includes a coal powder bin, which is connected to the coal injection gun of the furnace through a coal powder pipeline.

4. The sintering flue gas comprehensive utilization power generation and pollutant coordinated treatment system according to claim 1 is characterized in that: The sintering fume duct is also provided with a first fan, and the air jet gun is arranged at the bottom of the furnace.

5. The sintering flue gas comprehensive utilization power generation and pollutant coordinated treatment system according to claim 1 is characterized in that: The boiler also includes a separator and a tail flue, the separator is connected to the flue gas outlet of the furnace, the tail flue is connected to the flue gas outlet of the separator, an upper economizer, an SCR reactor, and a lower economizer are sequentially arranged in the tail flue along the flue gas flow direction, and the air preheater is arranged at the end of the tail flue.

6. The sintering flue gas comprehensive utilization power generation and pollutant coordinated treatment system according to claim 5 is characterized in that: The separator is provided with a denitration spray gun, and the denitration spray gun is connected with a denitration agent bin through a pipeline.

7. The sintering fume comprehensive utilization power generation and pollutant coordinated treatment system according to claim 5 is characterized in that: A solid material outlet is provided at the bottom of the separator, and the solid material outlet is connected to the furnace through a solid material pipeline.

8. The sintering fume comprehensive utilization power generation and pollutant coordinated treatment system according to claim 1 is characterized in that: The desulfurization mechanism comprises an activated coke desulfurization device, and an outlet end of the activated coke desulfurization device is connected to a chimney.

9. The sintering fume comprehensive utilization power generation and pollutant coordinated treatment system according to claim 8 is characterized in that: The desulfurization mechanism also includes an activated coke regeneration device and an acid-making unit. The discharge end of the activated coke regeneration device is connected to the feed end of the activated coke desulfurization device through a first activated coke chain bucket conveyor, and the discharge end of the activated coke desulfurization device is connected to the feed end of the activated coke regeneration device through a second activated coke chain bucket conveyor; the acid-making unit is connected to the activated coke regeneration device.

10. The sintering flue gas comprehensive utilization power generation and pollutant coordinated treatment system according to claim 1 is characterized in that: The dust collector is a bag dust collector, and a second fan is arranged on the pipeline between the dust collector and the desulfurization mechanism.

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