Process for the recovery of by-products from sintering off-gas desulphurization

Abstract

The application discloses a sintering flue gas desulfurization by-product recovery method and relates to the technical field of steel smelting; the method comprises the following steps: S1, first semi-dry desulfurization ash is mixed with first sintering raw materials, and then ignition combustion is performed to collect first flue gas; the first flue gas is subjected to a gypsum desulfurization process to prepare gypsum and desulfurization wastewater; second semi-dry desulfurization ash is mixed with second sintering raw materials, and then ignition combustion is performed to collect second flue gas; the second flue gas is subjected to an activated carbon desulfurization and acid production process to prepare sulfuric acid solution and acid production wastewater; S2, after the desulfurization wastewater and the acid production wastewater are treated, batching water is prepared. According to the method, the by-products of sintering flue gas desulfurization are reused to sintering batching of the desulfurization process, and gypsum and concentrated sulfuric acid are produced through sintering flue gas treatment, so that a path is provided for treating desulfurization by-products and resource utilization, and the environmental protection effect of no desulfurization wastewater discharge, no desulfurization solid waste discharge and sintering flue gas ultra-low emission is achieved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of steel smelting, and particularly relates to a recovery method of sintering flue gas desulfurization by-products. BACKGROUND

[0002] In recent years, with the implementation of ultra-low emission in the steel industry, lime / limestone-gypsum desulfurization plus selective catalytic reduction denitrification, circulating fluidized bed or rotary spray semi-dry desulfurization plus selective catalytic reduction denitrification, activated carbon desulfurization and denitrification plus flue gas acid production, etc. sintering machine head flue gas treatment processes are widely used. However, each desulfurization process produces desulfurization by-products, such as lime / limestone-gypsum desulfurization thallium-containing wastewater, semi-dry desulfurization ash, activated carbon desulfurization and denitrification acid wastewater, etc., which are difficult to handle or utilize and have a large amount of production. The lime / limestone-gypsum desulfurization thallium-containing wastewater is difficult to be treated by the three-way box dosing system to meet the "Industrial Wastewater Thallium Pollutant Discharge Standard", the semi-dry desulfurization is difficult to be applied in the process due to unstable properties, the acid wastewater has high heavy metal content and is difficult to be treated, etc. The above situations cause more heavy environmental protection costs for the steel metallurgical industry, and even potential safety problems.

[0003] The related art discloses a method for recycling semi-dry desulfurization ash to sintering, but does not consider the comprehensive treatment of desulfurization by-products for sintering and smelting plants matched with different sintering flue gas treatment processes. SUMMARY

[0004] The purpose of the present application is to provide a recovery method of sintering flue gas desulfurization by-products to solve at least one aspect of the problems and defects in the background art.

[0005] Specifically, the present application provides a recovery method of sintering flue gas desulfurization by-products, comprising the following steps:

[0006] S1, mixing the first semi-dry desulfurization ash with the first sintering raw material and igniting and burning to collect the first flue gas;

[0007] The first part of the flue gas is subjected to a gypsum desulfurization process to produce gypsum and desulfurization wastewater;

[0008] The second semi-dry desulfurization ash is mixed with the second sintering raw material, ignited and burned, and the second flue gas is collected;

[0009] The remaining part of the second flue gas is subjected to an activated carbon desulfurization and acid production process to produce a sulfuric acid solution and acid production wastewater;

[0010] S2, treating the desulfurization wastewater and the acid production wastewater to produce a proportioning water;

[0011] The components of the first semi-dry desulfurization ash include at least one of calcium bisulfite, calcium carbonate, calcium hydroxide and calcium oxide;

[0012] The second semi-dry desulfurization ash comprises at least one of calcium sulfite hemihydrate, calcium carbonate, calcium hydroxide, and calcium oxide.

[0013] According to one technical solution of the recycling method of the present invention, at least the following beneficial effects are achieved:

[0014] Based on the characteristics of various desulfurization processes and the needs of sintering production, this invention innovatively provides a comprehensive solution for the recycling and utilization of sintering flue gas desulfurization byproducts. The process flow of this invention is simple, the implementation cost is low, it fully utilizes existing metallurgical sintering technology and equipment, requires no additional equipment investment, has good on-site implementability, and the generated gypsum or sulfuric acid solution can be used as industrial raw materials. Furthermore, it can reduce environmental protection operating costs during steel production, realizing a new approach for the comprehensive recycling of various sintering desulfurization byproducts in steel production.

[0015] According to some embodiments of the present invention, the first sintering raw material includes iron ore powder, raw material powder, alkaline material powder and water.

[0016] This invention involves thoroughly mixing iron ore powder, raw material powder, and alkaline material powder. The high-temperature sintering environment of the iron ore powder decomposes the main products of the semi-dry desulfurization ash into calcium oxide and sulfur oxides. Calcium oxide promotes the solid-phase reaction during sintering, while sulfur oxides are fed into the sintering machine head flue gas treatment along with the sintering flue gas. These sulfur oxides react with lime / limestone slurry and are forced to oxidize by air injection to form well-crystallized calcium sulfate dihydrate, i.e., gypsum. Alternatively, activated carbon adsorption and desorption can be used to prepare industrial-grade concentrated sulfuric acid. Simultaneously, wastewater generated from the lime / limestone-gypsum desulfurization process and the acid production process is clarified through natural sedimentation, then siphoned and pumped to the sintering mixer for reuse.

[0017] According to some embodiments of the present invention, the second sintering raw material includes iron ore powder, raw material powder, alkaline material powder and water.

[0018] According to some embodiments of the present invention, in step S1, the first sintering raw material is mixed to obtain spherical material; the diameter of the spherical material is 3mm to 5mm.

[0019] According to some embodiments of the present invention, in step S1, the second sintering raw material is mixed to obtain spherical material; the diameter of the spherical material is 3mm to 5mm.

[0020] According to some embodiments of the present invention, the ignition temperature after mixing the first sintering raw materials is 1100℃~1200℃.

[0021] According to some embodiments of the present invention, the ignition temperature after mixing the second sintering raw materials is 1100℃~1200℃.

[0022] According to some embodiments of the present invention, the mass fraction of semi-dry desulfurization ash in the spherical material is above 1%.

[0023] According to some embodiments of the present invention, the sulfuric acid solution has a mass fraction of 93% to 98%.

[0024] According to some embodiments of the present invention, the liquid-to-gas ratio after treatment by the gypsum desulfurization process is 35 mg / Nm³. 3 the following.

[0025] According to some embodiments of the present invention, the liquid-to-gas ratio after treatment by the activated carbon desulfurization and acid production process is 35 mg / Nm³. 3 the following.

[0026] According to some embodiments of the present invention, the pH of the feed wastewater is 6 to 8.

[0027] According to some embodiments of the present invention, the mass ratio of the batching wastewater to the sintering raw material is 5-6:100.

[0028] According to some embodiments of the present invention, the ignition and combustion are carried out in a sintering machine.

[0029] According to some embodiments of the present invention, the effective organic area of ​​the sintering machine can be 90m². 2 ~600m 2 .

[0030] According to some embodiments of the present invention, the thickness of the material layer during the ignition and combustion process is 700mm to 1000mm.

[0031] According to some embodiments of the present invention, the liquid-to-gas ratio of the gypsum desulfurization process is not less than 20 L / m³. 3 .

[0032] According to some embodiments of the present invention, the desulfurization wastewater is the top flow of gypsum slurry separated by a gypsum hydrocyclone and the bottom flow of the gas-liquid separator of a vacuum belt dewatering system. After entering a vertical flow thickening tank, the upper layer of the wastewater is visually clear and transparent after natural settling for more than 30 minutes.

[0033] According to some embodiments of the present invention, the desulfurization wastewater is siphoned and pumped to a sintering mixer and injected into the sintering raw materials, and is recycled at a rate of 5% to 6% of the sintering raw materials (mass fraction).

[0034] According to some embodiments of the present invention, the wastewater from the activated carbon desulfurization and acid production process is an acidic wastewater containing dust and sludge formed by washing and cooling sulfur-rich flue gas.

[0035] According to some embodiments of the present invention, the acidic wastewater, after being neutralized to a pH value of 7 by caustic soda or limestone-gypsum desulfurization raw material limestone slurry, is naturally settled in a vertical flow thickening tank for more than 30 minutes to produce a clear and transparent upper layer of wastewater.

[0036] According to some embodiments of the present invention, the acidic wastewater is siphoned and pumped to a sintering mixer and sprayed into the sintering raw materials, and is recycled at a spraying rate of 5% to 6% (mass fraction) of the sintering raw materials.

[0037] According to some embodiments of the present invention, the raw materials for the gypsum desulfurization process include lime or limestone. Detailed Implementation

[0038] The following will describe the concept and technical effects of the present invention clearly and completely with reference to embodiments, so as to fully understand the purpose, features and effects of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention.

[0039] In the description of this invention, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0040] Unless otherwise specified in the examples, the procedures should be performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0041] Example 1

[0042] This embodiment describes a method for recovering desulfurization byproducts from sintering flue gas, comprising the following steps:

[0043] S1. Semi-dry desulfurization ash is mixed with sintering raw materials in a certain proportion and reused in the sintering machine that matches the lime / limestone-gypsum desulfurization process for resource utilization.

[0044] Semi-dry desulfurization ash is transported by tanker truck to the sintering mixing yard and mixed evenly with dust collector ash from the sintering conveyor line, sintering return ore, and slag iron concentrate (mixed at a mass ratio of 1:2:2) to obtain a mixture. Then, 5% of semi-dry desulfurization ash (based on the total mass of the mixture) is added. The mixture with added desulfurization ash is transported by belt to the sintering pre-batching material batching system at a mass ratio of 10% of sintering iron ore powder. Then, it is conveyed by belt to the sintering batching system and fully mixed with coal powder, coke powder (fuel powder, mass ratio 3.4%), quicklime, lightly calcined dolomite alkaline material powder (mass ratio 9.2%), water, etc., to form spherical sintering material of 3m to 5mm.

[0045] The spherical sinters are fed into a sintering machine for ignition and negative pressure combustion. The effective area of ​​the sintering machine is 360m². 2 The ignition temperature is 1200℃, the material layer thickness is 1000mm, and the liquid-to-gas ratio of the flue gas fed into the sintering machine head is not less than 22L / m³. 3 The limestone-gypsum desulfurization tower was used to achieve a desulfurization rate of 10 mg / Nm³. 3 The resulting plaster is gypsum. The test data for the plaster is shown in Table 1; the test data in Table 1 indicates that the plaster's properties meet the national standard (GB / T37785-2019).

[0046] Table 1. Gypsum Test Data

[0047] Item Test data Attached water content / % 11.81 Calcium sulfate dihydrate / % 94.63 Chloride / (mg / kg) 197.60 Calcium sulfite hemihydrate / % 0.31 Water-soluble magnesium oxide / % 0.006 Water-soluble sodium oxide / % 0.005 pH 6.75

[0048] Semi-dry desulfurization ash is mixed with sintering raw materials in a certain proportion and reused in sintering machines that match activated carbon desulfurization-acid production processes for resource utilization;

[0049] Semi-dry desulfurization ash is transported by tanker truck to the sintering mixing yard and mixed evenly with dust removal ash, sintering return ore, and slag iron concentrate (mixed at a mass ratio of 1:2:2) to obtain a mixture. Then, 5% of semi-dry desulfurization ash (based on the total mass of the mixture) is added. The mixture with added desulfurization ash is transported by belt to the sintering pre-batching material for proportioning at a mass ratio of 10% of sintering iron ore powder. Then, it is conveyed by belt to the sintering batching system and fully mixed with coal powder, coke powder (fuel powder, mass ratio of 3.2%), quicklime, lightly calcined dolomite alkaline material powder (mass ratio of 9.5%), water, etc., to form spherical sintering material of 3m to 5mm.

[0050] The spherical sinters are fed into a sintering machine for ignition and negative pressure combustion. The effective area of ​​the sintering machine is 360m². 2 The ignition temperature is 1180℃, the material layer thickness is 950mm, and the flue gas from the sintering machine head is treated in an activated carbon desulfurization, denitrification, and acid production process to achieve a concentration of 35mg / Nm³. 3The following describes the production of industrial-grade concentrated sulfuric acid in the acid production process. The test data for the concentrated sulfuric acid are shown in Table 2. Table 2 indicates that the concentrated sulfuric acid meets the Class I standards of the national standard (GB / T534-2014).

[0051] Table 2. Concentrated sulfuric acid detection data

[0052] Item Test data Sulfuric acid mass percentage / % 96.37 Ash mass percentage / % 0 Iron mass percentage / % 0.0000007 Arsenic mass percentage / % 0.0000040 Mercury mass percentage / % 0.0000001 Lead mass percentage / % 0.0000005 Clarity / mm 80

[0053] S2, Lime / Limestone – Gypsum desulfurization wastewater, after sedimentation and clarification, is siphoned and pumped to the sintering plant as additive water:

[0054] The desulfurization wastewater is taken from the dewatering system in the lime / limestone-gypsum desulfurization process. The gypsum slurry in the tower is pumped to the gypsum hydrocyclone for the first solid-liquid separation, resulting in the top flow. The bottom flow, drawn by the gas-liquid separator of the vacuum belt dewatering system through the dewatering filter cloth, also enters the 50m³ desulfurization system. 3 After natural settling for more than 30 minutes in the vertical flow thickening tank, the settled solids are discharged from the bottom outlet and transported to the tower for recrystallization via a sludge screw pump. The upper layer of visibly clear and transparent wastewater is siphoned into the buffer tank and then discharged at a rate of 7m. 3 / h pumped to the sintering mixer and injected with 450m 2 It is used in the batching and mixing machine of sintering machine.

[0055] After the wastewater from the activated carbon desulfurization-acid production process is neutralized, precipitated, and clarified, it is siphoned and pumped to the sintering stage as water added to the batch.

[0056] The acidic wastewater containing dust and sludge generated during the washing and cooling of sulfur-rich flue gas in the activated carbon desulfurization-acidification process is pumped to a sedimentation tank. After neutralization to approximately pH 7 by the limestone slurry used in caustic soda or limestone-gypsum desulfurization, the wastewater is then passed through a 50m... 3 After natural settling for more than 30 minutes in the vertical flow thickening tank, the clear and transparent wastewater at the top is siphoned into the buffer tank and then discharged at a speed of 5m. 3 / h is sent to the sintering mixer and sprayed with 360m 2 It is used in the batching and mixing machine of sintering machine.

[0057] Example 2

[0058] This embodiment describes a method for recovering desulfurization byproducts from sintering flue gas, comprising the following steps:

[0059] S1. Semi-dry desulfurization ash is mixed with sintering raw materials in a certain proportion and reused in the sintering machine that matches the lime / limestone-gypsum desulfurization process for resource utilization.

[0060] Semi-dry desulfurization ash is transported by tanker truck to the sintering mixing yard and mixed evenly with dust removal ash, sintering return ore, and slag iron concentrate (mixed at a mass ratio of 1:2:2) to obtain a mixture. Then, 10% of the semi-dry desulfurization ash (based on the total mass of the mixture) is added. The mixture with added desulfurization ash is transported by belt to the sintering pre-batching material for proportioning according to a mass ratio of 10% of sintering iron ore powder. Then, it is conveyed by belt to the sintering batching system and fully mixed with fuel powder of coal powder and coke powder (mass ratio of 3.3%) and alkaline material powder of quicklime and lightly calcined dolomite (mass ratio of 8.7%) to form spherical sintering material of 3m to 5mm.

[0061] The spherical sinters are fed into a sintering machine for ignition and negative pressure combustion. The effective area of ​​the sintering machine is 360m². 2 The ignition temperature is 1130℃, the material layer thickness is 920mm, and the liquid-to-gas ratio of the flue gas fed into the sintering machine head is not less than 22L / m. 3 The limestone-gypsum desulfurization tower was used to achieve a desulfurization rate of 10 mg / Nm³. 3 The resulting plaster is gypsum. The test data for the plaster is shown in Table 3; the test data in Table 1 shows that the plaster indicators meet the national standard (GB / T37785-2019).

[0062] Table 3. Gypsum Test Data

[0063] Item Test data Attached water content / % 11.27 Calcium sulfate dihydrate / % 93.73 Chloride / (mg / kg) 165.27 Calcium sulfite hemihydrate / % 0.29 Water-soluble magnesium oxide / % 0.008 Water-soluble sodium oxide / % 0.005 pH 6.83

[0064] Semi-dry desulfurization ash is mixed with sintering raw materials in a certain proportion and reused in sintering machines that match activated carbon desulfurization-acid production processes for resource utilization;

[0065] Semi-dry desulfurization ash is transported by tanker truck to the sintering mixing yard and mixed evenly with dust removal ash, sintering return ore, and slag iron concentrate (mixed at a mass ratio of 1:2:2) to obtain a mixture. Then, 10% of the semi-dry desulfurization ash (based on the total mass of the mixture) is added. The mixture with added desulfurization ash is transported by belt to the sintering pre-batching material for proportioning according to a mass ratio of 10% of sintering iron ore powder. Then, it is conveyed by belt to the sintering batching system and fully mixed with fuel powder of coal powder and coke powder (mass ratio of 3.2%) and alkaline material powder of quicklime and lightly calcined dolomite (mass ratio of 8.3%) to form spherical sintering material of 3m to 5mm.

[0066] The spherical sinters are fed into a sintering machine for ignition and negative pressure combustion. The effective area of ​​the sintering machine is 360m². 2 The ignition temperature is 1120℃, the material layer thickness is 990mm, and the flue gas from the sintering machine head is treated in an activated carbon desulfurization, denitrification, and acid production process to achieve a concentration of 35mg / Nm³. 3The following describes the production of industrial-grade concentrated sulfuric acid in the acid manufacturing process. The test data for the concentrated sulfuric acid are shown in Table 2. Table 2 shows that the concentrated sulfuric acid meets the Class A quality standards of the national standard (GB / T534-2014). Table 4 also shows that the concentrated sulfuric acid meets the Class A quality standards of the national standard (GB / T534-2014).

[0067] Table 4. Detection data of concentrated sulfuric acid

[0068] Item Test data Sulfuric acid mass percentage / % 97.21 Ash mass percentage / % 0 Iron mass percentage / % 0.0000009 Arsenic mass percentage / % 0.0000037 Mercury mass percentage / % 0.0000003 Lead mass percentage / % 0.0000008 Clarity / mm 81

[0069] S2, Lime / Limestone – Gypsum desulfurization wastewater, after sedimentation and clarification, is siphoned and pumped to the sintering plant as additive water:

[0070] The desulfurization wastewater is taken from the dewatering system in the lime / limestone-gypsum desulfurization process. The gypsum slurry in the tower is pumped to the gypsum hydrocyclone for the first solid-liquid separation, resulting in the top flow. The bottom flow, drawn by the gas-liquid separator of the vacuum belt dewatering system through the dewatering filter cloth, also enters the 50m³ desulfurization system. 3 After natural settling for more than 30 minutes in the vertical flow thickening tank, the settled solids are discharged from the bottom outlet and transported to the tower for recrystallization via a sludge screw pump. The upper layer of visibly clear and transparent wastewater is siphoned into the buffer tank and then discharged at a speed of 6m. 3 / h pumped to the sintering mixer and injected with 450m 2 It is used in the batching and mixing machine of sintering machine.

[0071] After the wastewater from the activated carbon desulfurization-acid production process is neutralized, precipitated, and clarified, it is siphoned and pumped to the sintering stage as water added to the batch.

[0072] The acidic wastewater containing dust and sludge generated during the washing and cooling of sulfur-rich flue gas in the activated carbon desulfurization-acidification process is pumped to a sedimentation tank. After neutralization to approximately pH 7 by the limestone slurry used in caustic soda or limestone-gypsum desulfurization, the wastewater is then passed through a 50m... 3 After natural settling for more than 30 minutes in the vertical flow thickening tank, the clear and transparent wastewater at the top is siphoned into the buffer tank and then discharged at a speed of 4m. 3 / h is sent to the sintering mixer and sprayed with 360m 2 It is used in the batching and mixing machine of sintering machine.

[0073] In summary, this invention provides a comprehensive recycling and utilization method for sintering flue gas desulfurization byproducts. By matching three sintering machines with ash / limestone-gypsum flue gas desulfurization processes, activated carbon desulfurization and denitrification processes, and circulating fluidized bed desulfurization processes respectively, the byproducts generated by each process are recovered for sintering utilization. Based on the characteristics of desulfurization ash—high calcium and high sulfur content and its easy decomposition at high temperatures—it is reused in high-temperature sintering processes matched with lime / limestone-gypsum flue gas desulfurization or activated carbon desulfurization and denitrification processes, achieving the reuse of calcium and sulfur. Gravity sedimentation is used to achieve solid-liquid separation for the reuse of lime / limestone-gypsum flue gas desulfurization wastewater. The lime / limestone-gypsum flue gas desulfurization raw material slurry is used to neutralize activated carbon desulfurization and denitrification acid production system wastewater, followed by gravity sedimentation for solid-liquid separation and reuse of acid production wastewater.

[0074] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are 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 within the protection scope of the present invention.

Claims

1. A method for recovering byproducts from sintering flue gas desulfurization, characterized in that, Includes the following steps: S1. Mix the first semi-dry desulfurization ash with the first sintering raw material and ignite it for combustion, then collect the first flue gas. The first flue gas is subjected to gypsum desulfurization process to produce gypsum and desulfurization wastewater; The first semi-dry desulfurization ash is mixed with the first sintering raw material in a certain proportion and reused in the sintering machine that matches the lime / limestone-gypsum desulfurization process for resource utilization. The mass of the first semi-dry desulfurization ash is 5% of the mass of the first sintering raw material. The spherical sintering material is fed into the sintering machine for ignition and negative pressure combustion. The effective area of ​​the sintering machine is 360m². 2 The ignition temperature is 1200℃, the material layer thickness is 1000mm, and the liquid-to-gas ratio of the flue gas fed into the sintering machine head is not less than 22L / m³. 3 The limestone-gypsum desulfurization tower was used to desulfurize the gas to achieve a liquid-to-gas ratio of 10 mg / Nm³. 3 This generates gypsum and desulfurization wastewater; The first semi-dry desulfurization ash comprises at least one of calcium sulfite hemihydrate, calcium carbonate, calcium hydroxide, and calcium oxide. The first sintering raw material includes iron ore powder, raw material powder, alkaline material powder, and water; The treatment method for the desulfurization wastewater includes: the desulfurization wastewater is taken from the dewatering system in lime / limestone-gypsum desulfurization; the gypsum slurry in the tower is pumped to the gypsum hydrocyclone for the first solid-liquid separation; the top flow after the first solid-liquid separation; and the bottom flow drawn by the gas-liquid separator of the vacuum belt dewatering system through the dewatering filter cloth, both enter a 50m... 3 After the vertical flow thickener is in the thickener, allow it to settle naturally for more than 30 minutes. The second semi-dry desulfurization ash is mixed with the second sintering raw material and then ignited and burned to collect the second flue gas. The second flue gas is subjected to activated carbon desulfurization and acid production process to produce sulfuric acid solution and acid production wastewater. The second semi-dry desulfurization ash is mixed with the second sintering raw material in a certain proportion and reused in the sintering machine that matches the activated carbon desulfurization-acid production process for resource utilization. The mass of the second semi-dry desulfurization ash is 5% of the mass of the second sintering raw material. The spherical sintering material is fed into the sintering machine for ignition and negative pressure combustion. The effective area of ​​the sintering machine is 360m². 2 The ignition temperature is 1180℃, the material layer thickness is 950mm, and the flue gas from the sintering machine head is treated in an activated carbon desulfurization, denitrification, and acid production process to achieve a liquid-to-gas ratio of 35mg / Nm³. 3 The following processes generate industrial-grade concentrated sulfuric acid and acid production wastewater. The second semi-dry desulfurization ash comprises at least one of calcium sulfite hemihydrate, calcium carbonate, calcium hydroxide, and calcium oxide. The second sintering raw material includes iron ore powder, raw material powder, alkaline material powder, and water; The treatment method for the acid production wastewater includes: neutralizing the acid production wastewater to a pH value of approximately 7 using limestone slurry, the raw material for caustic soda or limestone-gypsum desulfurization, and then passing it through a 50m... 3 After the vertical flow thickener is in the thickener, allow it to settle naturally for more than 30 minutes. The first semi-dry desulfurization ash and the second semi-dry desulfurization ash are sourced from the circulating fluidized bed desulfurization process; S2. After treating the desulfurization wastewater and the acid production wastewater, the batching water is prepared. The mass ratio of the water used in the batching process to the sintering raw materials is 5~6:100; The water in the first sintering raw material and the second sintering raw material includes the batching water.

2. The method for recovering desulfurization byproducts from sintering flue gas according to claim 1, characterized in that, In step S1, the first sintering raw material is mixed to obtain spherical material; the diameter of the spherical material is 3mm~5mm; in step S1, the second sintering raw material is mixed to obtain spherical material; the diameter of the spherical material is 3mm~5mm.

3. The method for recovering sintering flue gas desulfurization byproducts according to claim 1, characterized in that, The sulfuric acid solution has a mass fraction of 93% to 98%.

4. The method for recovering sintering flue gas desulfurization byproducts according to claim 1, characterized in that, The pH of the water used for mixing the ingredients is 6-8.