System and method for generating power by utilizing sulfur dioxide in boiler flue gas

Abstract

The invention discloses a system and a method for generating power by utilizing sulfur dioxide in boiler flue gas. The system comprises a boiler induced draft fan rear flue, a sulfur dioxide absorption module and a flue gas emission module, the method comprises the following steps: flue gas discharged from a rear flue of a boiler induced draft fan enters a first inlet of a sulfur dioxide absorption module, an iodine solution of the sulfur dioxide absorption module is sprayed out from an atomizing nozzle from top to bottom and the flue gas from bottom to top, and a filler layer is arranged between the atomizing nozzle and the flue gas inlet to increase the contact between the flue gas and the iodine solution; iodine, sulfur dioxide and water react to generate a hydrogen iodide solution and a sulfuric acid solution, and flue gas with absorbed sulfur dioxide is discharged into the flue gas discharge module from a first outlet of the sulfur dioxide absorption module. Through the closed-loop process of iodine solution absorption-hydrogen iodide decomposition-hydrogen fuel cell power generation, the limitation that only pollutant removal is concerned in the traditional desulfurization technology is broken through.

Description

Technical Field

[0001] This invention belongs to the fields of coal-fired boilers, hydrogen production, and environmental protection technology, and specifically relates to a system and method for generating electricity using sulfur dioxide from boiler flue gas. Background Technology

[0002] Boiler flue gas contains sulfur dioxide, which is an air pollutant. Boilers need to be equipped with a dedicated desulfurization system to remove sulfur dioxide from the flue gas. Currently, boiler desulfurization mainly uses limestone wet desulfurization systems. This method increases the operating cost of boilers, the gypsum produced has low application value, and the limestone production process increases carbon emissions. Summary of the Invention

[0003] This invention provides a system and method for generating electricity using sulfur dioxide from boiler flue gas, aiming to overcome the shortcomings of existing technologies.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A system for generating electricity using sulfur dioxide from boiler flue gas includes a flue duct after the boiler induced draft fan, a sulfur dioxide absorption module, and a flue gas emission module.

[0006] The outlet of the flue after the boiler induced draft fan is connected to the first inlet of the sulfur dioxide absorption module, and the first outlet of the sulfur dioxide absorption module is connected to the flue gas emission module. The sulfur dioxide absorption module uses iodine solution as the sulfur dioxide absorption medium.

[0007] A further improvement of the present invention is that it also includes a hydrogen iodide and sulfuric acid separation module, a sulfuric acid collection module, and a hydrogen iodide collection module; the second outlet of the sulfur dioxide absorption module is connected to the inlet of the hydrogen iodide and sulfuric acid separation module, the first outlet of the hydrogen iodide and sulfuric acid separation module is connected to the inlet of the hydrogen iodide collection module, and the second outlet of the hydrogen iodide and sulfuric acid separation module is connected to the sulfuric acid collection module.

[0008] A further improvement of the present invention is that it also includes a hydrogen iodide heating module and a hydrogen iodide decomposer, wherein the outlet of the hydrogen iodide collection module is connected to the inlet of the hydrogen iodide heating module, and the outlet of the hydrogen iodide heating module is connected to the inlet of the hydrogen iodide decomposer.

[0009] A further improvement of the present invention is that it also includes a hydrogen separation module and a hydrogen storage module. The hydrogen separation module is equipped with a condensation device. The outlet of the hydrogen iodide decomposer is connected to the inlet of the hydrogen separation module. The mixed solution outlet of the hydrogen separation module is connected to the second inlet of the sulfur oxide absorption module. The hydrogen outlet of the hydrogen separation module is connected to the inlet of the hydrogen storage module.

[0010] A further improvement of the present invention is that it also includes a hydrogen fuel cell module and a power transmission module, wherein the outlet of the hydrogen storage module is connected to the inlet of the hydrogen fuel cell module, and the power transmission end of the hydrogen fuel cell module is connected to the power transmission module.

[0011] A further improvement of the present invention is that the heat source of the hydrogen iodide heating module comes from the high-temperature boiler flue gas, steam or electricity provided by the boiler.

[0012] A method for generating electricity using sulfur dioxide from boiler flue gas, the method being based on the aforementioned system for generating electricity using sulfur dioxide from boiler flue gas, comprising:

[0013] The flue gas exiting from the boiler induced draft fan's flue enters the first inlet of the sulfur dioxide absorption module. The iodine solution in the sulfur dioxide absorption module is sprayed from the atomizing nozzle from top to bottom, while the flue gas rises from bottom to top. A packing layer is set between the atomizing nozzle and the flue gas inlet to increase the contact between the flue gas and the iodine solution. Iodine, sulfur dioxide, and water react to generate hydrogen iodide solution and sulfuric acid solution. The flue gas that has absorbed sulfur dioxide is discharged from the first outlet of the sulfur dioxide absorption module into the emission flue gas module.

[0014] A further improvement of the present invention is that it further includes: the hydrogen iodide solution and sulfuric acid solution discharged from the second outlet of the sulfur dioxide absorption module enter the hydrogen iodide and sulfuric acid separation module and are separated into hydrogen iodide solution and sulfuric acid solution; the hydrogen iodide solution enters the hydrogen iodide collection module from the first outlet of the hydrogen iodide and sulfuric acid separation module, and the sulfuric acid solution enters the sulfuric acid collection module from the second outlet of the hydrogen iodide and sulfuric acid separation module.

[0015] A further improvement of the present invention is that it further includes: the hydrogen iodide solution discharged from the hydrogen iodide collection module enters the hydrogen iodide heating module and is heated to above 500°C to form a mixed gas of hydrogen iodide and water vapor, and the mixed gas enters the hydrogen iodide decomposer, where it is partially decomposed to form a mixed gas of hydrogen iodide gas, water vapor, iodine vapor and hydrogen.

[0016] A further improvement of the present invention is that it further includes: after the mixed gas discharged from the hydrogen iodide decomposer enters the hydrogen separation module and is cooled, the hydrogen iodide gas, water vapor, and iodine vapor condense into a mixed solution of hydrogen iodide and iodine. The mixed solution is discharged into the sulfur dioxide absorption module from the second inlet of the sulfur dioxide absorption module and used again to absorb sulfur dioxide gas in the boiler flue gas. The hydrogen discharged from the hydrogen separation module enters the hydrogen storage module for storage.

[0017] The hydrogen fuel cell module consumes hydrogen discharged from the hydrogen storage module to generate electricity, and the electrical energy generated by the hydrogen fuel cell module is fed into the power grid through the power transmission module.

[0018] Compared with the prior art, the present invention has at least the following beneficial technical effects:

[0019] (I) The contribution of core technologies to "synergistic desulfurization and hydrogen production power generation"

[0020] This invention overcomes the limitation of traditional desulfurization technologies that only focus on pollutant removal through a closed-loop process of "iodine solution absorption - hydrogen iodide decomposition - hydrogen fuel cell power generation." Specific technical means include:

[0021] 1. Selection of iodine solution as absorption medium:

[0022] Traditional limestone wet desulfurization relies on the reaction of CaCO3 and SO2 to produce CaSO4 (gypsum). This invention, however, uses iodine solution (I2) as the absorbent. Through the chemical reaction SO2 + I2 + 2H2O → 2HI + H2SO4, SO2 is converted into highly reactive hydrogen iodide (HI) and industrial-grade sulfuric acid (H2SO4). This conversion process not only achieves desulfurization but also transforms pollutants into raw materials (HI) and high-value-added chemicals (H2SO4) that can be used for energy production, thus solving the resource waste problem of traditional methods where "desulfurization is the final treatment."

[0023] 2. Recycling and decomposition of hydrogen iodide to produce hydrogen:

[0024] The system uses a hydrogen iodide heating module (above 500℃) and a decomposer to decompose HI into H2 and... The I2 is condensed and refluxed back to the absorption module for reuse, eliminating the need for additional iodine feedstock. This closed-loop design significantly reduces operating costs, whereas traditional desulfurizing agents (such as limestone) are disposable consumables that require continuous procurement.

[0025] 3. Cascaded utilization of energy:

[0026] The heat source for the hydrogen iodide heating module comes directly from the boiler's own high-temperature flue gas, steam, or electricity, without the need for additional external energy. For example, by using the waste heat from the boiler exhaust (typically at 150-200℃) to preheat the hydrogen iodide solution, and then heating it to the decomposition temperature with a small amount of electricity or steam, efficient cascade utilization of energy is achieved, improving the overall system's energy conversion efficiency.

[0027] (II) Technical support for "high value-added by-products and power grid peak shaving"

[0028] Sulfuric acid recycling: The H2SO4 produced by the separation module can reach a concentration of over 98%, which can be directly used as an industrial raw material (such as fertilizer and chemical synthesis). The market value of each ton of sulfuric acid is about 300-500 yuan, while the value of traditional gypsum by-products is only 20-50 yuan per ton, resulting in a significant improvement in economic benefits.

[0029] The flexible power supply of hydrogen fuel cells: The hydrogen storage module can release hydrogen to generate electricity according to the grid load demand, supplementing the grid power during peak electricity consumption periods (such as summer afternoons), while traditional thermal power plants have a slow response time to load adjustments. The hydrogen fuel cell power generation process emits no pollutants and has a response time of less than 10 seconds, improving the grid's frequency regulation and peak shaving capabilities.

[0030] (III) Summary of Creative Contributions

[0031] The ingenuity of this invention lies in the organic coupling of pollutant treatment (desulfurization) and energy production (hydrogen production for power generation) through an iodine cycle process, specifically embodied in:

[0032] Process closed-loop innovation: For the first time, the oxidation-reduction properties of iodine solution are utilized to achieve the cyclical transformation of SO2→HI→H2+I2, breaking through the traditional linear desulfurization model of "input-consumption-waste".

[0033] Energy cascade utilization: Deeply integrate boiler waste heat with hydrogen fuel cell technology to realize the conversion of low-grade thermal energy into high-grade electrical energy;

[0034] Synergy between economic development and environmental protection: By adding value to by-products and reducing energy consumption, the industry pain point of "high environmental costs" in desulfurization technology has been solved, providing a replicable technical path for the low-carbon transformation of the thermal power industry.

[0035] The combined application of the above-mentioned technical means makes the present invention significantly superior to the existing technology in terms of desulfurization efficiency, resource utilization rate and economic benefits, and it has outstanding substantive features and significant progress. Attached Figure Description

[0036] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 This is a structural block diagram of a system for generating electricity using sulfur dioxide from boiler flue gas, according to the present invention.

[0038] Explanation of reference numerals in the attached figures:

[0039] 1. Boiler induced draft fan flue; 2. Sulfur dioxide absorption module; 3. Hydrogen iodide and sulfuric acid separation module; 4. Sulfuric acid collection module; 5. Hydrogen iodide collection module; 6. Hydrogen iodide heating module; 7. Hydrogen iodide decomposer; 8. Hydrogen separation module; 9. Hydrogen storage module; 10. Hydrogen fuel cell module; 11. Flue gas emission module; 12. Power transmission module. Detailed Implementation

[0040] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0041] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0042] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0043] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0044] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0045] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0046] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0047] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0048] The accompanying drawings illustrate various structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0049] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0050] Example 1

[0051] like Figure 1 As shown, the present invention provides a system for generating electricity using sulfur dioxide from boiler flue gas, including a boiler induced draft fan flue 1, a sulfur dioxide absorption module 2, and a flue gas emission module 11; the outlet of the boiler induced draft fan flue 1 is connected to the first inlet of the sulfur dioxide absorption module 2, and the first outlet of the sulfur dioxide absorption module 2 is connected to the emission flue gas module 11, wherein the sulfur dioxide absorption module 2 uses an iodine solution as the sulfur dioxide absorption medium.

[0052] In this embodiment, the system also includes a hydrogen iodide and sulfuric acid separation module 3, a sulfuric acid collection module 4, and a hydrogen iodide collection module 5; the second outlet of the sulfur dioxide absorption module 2 is connected to the inlet of the hydrogen iodide and sulfuric acid separation module 3, the first outlet of the hydrogen iodide and sulfuric acid separation module 3 is connected to the inlet of the hydrogen iodide collection module 5, and the second outlet of the hydrogen iodide and sulfuric acid separation module 3 is connected to the sulfuric acid collection module 4.

[0053] In this embodiment, a hydrogen iodide heating module 6 and a hydrogen iodide decomposer 7 are also included. The outlet of the hydrogen iodide collection module 5 is connected to the inlet of the hydrogen iodide heating module 6, and the outlet of the hydrogen iodide heating module 6 is connected to the inlet of the hydrogen iodide decomposer 7.

[0054] In this embodiment, a hydrogen separation module 8 and a hydrogen storage module 9 are also included. The hydrogen separation module 8 is equipped with a condensation device. The outlet of the hydrogen iodide decomposer 7 is connected to the inlet of the hydrogen separation module 8. The mixed solution outlet of the hydrogen separation module 8 is connected to the second inlet of the sulfur oxide absorption module 2. The hydrogen outlet of the hydrogen separation module 8 is connected to the inlet of the hydrogen storage module 9.

[0055] In this embodiment, a hydrogen fuel cell module 10 and a power transmission module 12 are also included. The outlet of the hydrogen storage module 9 is connected to the inlet of the hydrogen fuel cell module 10, and the power transmission end of the hydrogen fuel cell module 10 is connected to the power transmission module 12.

[0056] In this embodiment, the heat source for the hydrogen iodide heating module 6 comes from the high-temperature boiler flue gas, steam, or electricity provided by the boiler.

[0057] Example 2

[0058] like Figure 1 As shown, the present invention provides a method for generating electricity using sulfur dioxide from boiler flue gas, comprising:

[0059] The flue gas exiting from the boiler induced draft fan after flue 1 enters the first inlet of the sulfur dioxide absorption module 2. The iodine solution of the sulfur dioxide absorption module 2 is sprayed out from the atomizing nozzle from top to bottom, while the flue gas rises from bottom to top. A packing layer is set between the atomizing nozzle and the flue gas inlet to increase the contact between the flue gas and the iodine solution. Iodine, sulfur dioxide, and water react to generate hydrogen iodide solution and sulfuric acid solution. The flue gas that has absorbed sulfur dioxide is discharged from the first outlet of the sulfur dioxide absorption module 2 into the exhaust flue gas module 11.

[0060] In this embodiment, the hydrogen iodide solution and sulfuric acid solution discharged from the second outlet of the sulfur dioxide absorption module 2 are further introduced into the hydrogen iodide and sulfuric acid separation module 3 and separated into hydrogen iodide solution and sulfuric acid solution. The hydrogen iodide solution enters the hydrogen iodide collection module 5 from the first outlet of the hydrogen iodide and sulfuric acid separation module 3, and the sulfuric acid solution enters the sulfuric acid collection module 4 from the second outlet of the hydrogen iodide and sulfuric acid separation module 3.

[0061] In this embodiment, the hydrogen iodide solution discharged from the hydrogen iodide collection module 5 enters the hydrogen iodide heating module 6 and is heated to above 500°C to form a mixed gas of hydrogen iodide and water vapor. The mixed gas enters the hydrogen iodide decomposer 7 and is partially decomposed to form a mixed gas of hydrogen iodide gas, water vapor, iodine vapor and hydrogen.

[0062] In this embodiment, the mixture discharged from the hydrogen iodide decomposer 7 is cooled in the hydrogen separation module 8, where the hydrogen iodide gas, water vapor, and iodine vapor condense into a mixed solution of hydrogen iodide and iodine. The mixed solution is discharged into the sulfur dioxide absorption module 2 from the second inlet of the sulfur dioxide absorption module 2 and used again to absorb sulfur dioxide gas in the boiler flue gas. The hydrogen discharged from the hydrogen separation module 8 is stored in the hydrogen storage module 9. The hydrogen fuel cell module 10 consumes the hydrogen discharged from the hydrogen storage module 9 to generate electricity, and the electrical energy generated by the hydrogen fuel cell module 10 is fed into the power grid through the power transmission module 12.

[0063] Example 3

[0064] Case Background: A 2×300MW coal-fired power plant originally used a limestone wet desulfurization system, with an annual coal consumption of approximately 2 million tons, an SO2 concentration of 2000 mg / m3 in the flue gas, and annual SO2 emissions of approximately 4800 tons. In 2024, it was upgraded to the system described in this invention. Specific implementation data are as follows:

[0065] Desulfurization efficiency and pollutant emission reduction:

[0066] After the upgrade, the SO2 removal rate stabilized at over 98%, and the SO2 concentration in the flue gas at the outlet dropped to below 40 mg / m3, which is better than the national ultra-low emission standard (50 mg / m3). The annual SO2 emission reduction is about 4,704 tons, and the limestone consumption is reduced by about 12,000 tons / year (Ca / S molar ratio of 1.03 in the traditional method), which corresponds to a reduction of about 3,000 tons / year in carbon emissions from limestone mining and transportation.

[0067] Energy conversion and economic benefits:

[0068] The system processes 1.2 million cubic meters of flue gas per hour, generating approximately 8 tons of HI solution per hour, and producing about 50 Nm³ of hydrogen after decomposition. 3 / h (standard cubic meters);

[0069] The hydrogen fuel cell has a power generation efficiency (LHV) of about 45%, and can generate about 3.5 kWh of electricity per cubic meter of H2. The hourly power generation is about 175 kWh, and the annual power generation is about 1.533 million kWh (based on 8,760 hours of operation per year), which can meet the annual electricity needs of about 1,500 households.

[0070] The by-product production of 98% concentrated sulfuric acid is approximately 15,000 tons per year. Based on a market price of 400 yuan per ton, the annual revenue is approximately 6 million yuan. The reduction in desulfurization operating costs (limestone procurement and solid waste treatment) is approximately 8 million yuan per year, resulting in a comprehensive annual economic benefit of approximately 14 million yuan.

[0071] Energy self-sufficiency rate:

[0072] The hydrogen iodide heating module provides heat by recovering waste heat from the boiler's high-temperature flue gas (approximately 150°C) and steam extracted from the turbine (0.5MPa saturated steam). The heating energy self-sufficiency rate reaches 85%, requiring only a small amount of supplementary electricity (approximately 5% of the total power generation of the system), thus achieving efficient energy recycling.

[0073] Compared with traditional desulfurization technologies:

[0074]

[0075] Example 4

[0076] Case Background: A large chemical enterprise produces 1 million tons of sulfuric acid annually. Its sulfur-to-sulfuric acid unit generates SO2-containing tail gas (concentration approximately 3000 mg / m³) during the conversion process. Originally, ammonia absorption was used for desulfurization, consuming 8000 tons of liquid ammonia annually and producing approximately 12,000 tons of ammonium sulfate (fertilizer grade) as a byproduct. However, this method suffered from secondary pollution due to ammonia escape and low added value of the byproducts. In 2025, the system of this invention was adopted to upgrade the tail gas treatment process, designed to treat a flue gas volume of 500,000 Nm³. 3 / h.

[0077] Key implementation data

[0078] Desulfurization and resource conversion efficiency

[0079] SO2 removal rate: The system uses a two-stage packed absorption tower (iodine solution concentration 15%) with countercurrent gas-liquid contact, achieving an SO2 absorption rate of 99.5%, reducing the outlet concentration to 15 mg / m3, which is better than the limit of 400 mg / m3 in the "Integrated Emission Standard of Air Pollutants" (GB16297-1996). 3 );

[0080] Material conversion: The annual SO2 processing capacity is 500,000 Nm3 / h × 3000 mg / m3 × 99.5% × 8760h = 13140 tons, which generates 28600 tons of HI solution through reaction and produces 820 tons of hydrogen after decomposition (theoretical yield: 1 mol SO2 → 1 mol H2).

[0081] Energy and economic benefits

[0082] Power generation efficiency: The hydrogen fuel cell uses proton exchange membrane (PEMFC) technology, with a power generation efficiency of 48% and an annual power generation of 820 tons × 11126 Nm³. 3 / ton×3.5kWh / Nm 3 ×48%≈15.6 million kWh. Based on the electricity price of 0.55 yuan / kWh for self-owned power plants of chemical enterprises, the annual revenue is about 8.58 million yuan.

[0083] Sulfuric acid recovery: 13,140 tons of 98% concentrated sulfuric acid were produced as a by-product × (98 / 64) = 20,200 tons, which can be used as raw material for the company's internal phosphoric acid production (replacing purchased sulfuric acid), saving 20,200 tons × 500 yuan / ton in procurement costs per year = 10.1 million yuan.

[0084] Cost savings: Savings on liquid ammonia purchase costs (8,000 tons × 3,000 yuan / ton = 24 million yuan) and ammonium sulfate disposal costs (12,000 tons × 100 yuan / ton = 1.2 million yuan), resulting in a comprehensive annual economic benefit of 8.58 + 10.10 + 24 million + 1.2 million = 43.88 million yuan.

[0085] Technological Adaptability Innovation

[0086] Heat source coupling: The medium-pressure steam (4.0MPa, 450℃) from the sulfuric acid unit conversion process is used as the heat source for the hydrogen iodide heating module, achieving 100% self-sufficiency in heating energy consumption and realizing the cascade utilization of steam (the waste heat of steam after power generation is used for heating in the plant area).

[0087] Corrosion control: The absorption tower and separation module are made of titanium alloy, which can withstand corrosion from high concentrations of iodine solution and sulfuric acid. The expected service life of the equipment is 15 years (compared to 8 years for traditional ammonia desulfurization equipment).

[0088] Automated control: The PLC system adjusts the concentration of iodine solution and flue gas flow in real time. When the SO2 concentration fluctuates by ±500mg / m3, the system response time is less than 30 seconds, ensuring stable outlet concentration.

[0089] Advantages compared to traditional processes

[0090]

[0091]

[0092] Case Value

[0093] This case study verifies the system's stability in treating high-concentration SO2 tail gas (3000 mg / m3). Through the integrated design of "tail gas desulfurization-hydrogen cogeneration-sulfuric acid reuse", it not only solves the pain points of high desulfurization costs and low value of by-products in the chemical industry, but also realizes the internal circulation of energy and resources (sulfuric acid is reused in production and electricity is used to supplement the plant's power grid), providing a demonstration path for the resource utilization of high-concentration SO2 industrial tail gas.

[0094] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0095] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A system for generating electricity using sulfur dioxide from boiler flue gas, characterized in that, It includes a boiler induced draft fan flue (1), a sulfur dioxide absorption module (2), and a flue gas emission module (11); The outlet of the flue (1) after the boiler induced draft fan is connected to the first inlet of the sulfur dioxide absorption module (2), and the first outlet of the sulfur dioxide absorption module (2) is connected to the exhaust gas module (11). The sulfur dioxide absorption medium used in the sulfur dioxide absorption module (2) is iodine solution.

2. The system for generating electricity using sulfur dioxide from boiler flue gas according to claim 1, characterized in that, It also includes a hydrogen iodide and sulfuric acid separation module (3), a sulfuric acid collection module (4) and a hydrogen iodide collection module (5); the second outlet of the sulfur dioxide absorption module (2) is connected to the inlet of the hydrogen iodide and sulfuric acid separation module (3), the first outlet of the hydrogen iodide and sulfuric acid separation module (3) is connected to the inlet of the hydrogen iodide collection module (5), and the second outlet of the hydrogen iodide and sulfuric acid separation module (3) is connected to the sulfuric acid collection module (4).

3. A system for generating electricity using sulfur dioxide from boiler flue gas according to claim 2, characterized in that, It also includes a hydrogen iodide heating module (6) and a hydrogen iodide decomposer (7), with the outlet of the hydrogen iodide collection module (5) connected to the inlet of the hydrogen iodide heating module (6) and the outlet of the hydrogen iodide heating module (6) connected to the inlet of the hydrogen iodide decomposer (7).

4. A system for generating electricity using sulfur dioxide from boiler flue gas according to claim 3, characterized in that, It also includes a hydrogen separation module (8) and a hydrogen storage module (9). The hydrogen separation module (8) is equipped with a condenser. The outlet of the hydrogen iodide decomposer (7) is connected to the inlet of the hydrogen separation module (8). The mixed solution outlet of the hydrogen separation module (8) is connected to the second inlet of the sulfur oxide absorption module (2). The hydrogen outlet of the hydrogen separation module (8) is connected to the inlet of the hydrogen storage module (9).

5. A system for generating electricity using sulfur dioxide from boiler flue gas according to claim 4, characterized in that, It also includes a hydrogen fuel cell module (10) and a power transmission module (12). The outlet of the hydrogen storage module (9) is connected to the inlet of the hydrogen fuel cell module (10), and the power transmission end of the hydrogen fuel cell module (10) is connected to the power transmission module (12).

6. A system for generating electricity using sulfur dioxide from boiler flue gas according to claim 3, characterized in that, The heat source for the hydrogen iodide heating module (6) comes from the high-temperature boiler flue gas, steam or electricity provided by this boiler.

7. A method for generating electricity using sulfur dioxide from boiler flue gas, characterized in that, This method, based on a system for generating electricity using sulfur dioxide from boiler flue gas as described in claim 5, includes: The flue gas coming out from the flue (1) after the boiler induced draft fan enters the first inlet of the sulfur dioxide absorption module (2). The iodine solution of the sulfur dioxide absorption module (2) is sprayed out from the atomizing nozzle from top to bottom, while the flue gas comes from bottom to top. A packing layer is set between the atomizing nozzle and the flue gas inlet to increase the contact between the flue gas and the iodine solution. Iodine, sulfur dioxide and water react to generate hydrogen iodide solution and sulfuric acid solution. The flue gas that has absorbed sulfur dioxide is discharged from the first outlet of the sulfur dioxide absorption module (2) to the emission flue gas module (11).

8. A method for generating electricity using sulfur dioxide from boiler flue gas according to claim 7, characterized in that, Also includes: The hydrogen iodide solution and sulfuric acid solution discharged from the second outlet of the sulfur dioxide absorption module (2) enter the hydrogen iodide and sulfuric acid separation module (3) and are separated into hydrogen iodide solution and sulfuric acid solution. The hydrogen iodide solution enters the hydrogen iodide collection module (5) from the first outlet of the hydrogen iodide and sulfuric acid separation module (3), and the sulfuric acid solution enters the sulfuric acid collection module (4) from the second outlet of the hydrogen iodide and sulfuric acid separation module (3).

9. A method for generating electricity using sulfur dioxide from boiler flue gas according to claim 8, characterized in that, Also includes: The hydrogen iodide solution discharged from the hydrogen iodide collection module (5) enters the hydrogen iodide heating module (6) and is heated to above 500°C to form a mixed gas of hydrogen iodide and water vapor. The mixed gas enters the hydrogen iodide decomposer (7) and is partially decomposed to form a mixed gas of hydrogen iodide, water vapor, iodine vapor and hydrogen.

10. A method for generating electricity using sulfur dioxide from boiler flue gas according to claim 9, characterized in that, Also includes: The mixed gas discharged from the hydrogen iodide decomposer (7) enters the hydrogen separation module (8) and is cooled. The hydrogen iodide gas, water vapor, and iodine vapor condense into a mixed solution of hydrogen iodide and iodine. The mixed solution is discharged from the second inlet of the sulfur dioxide absorption module (2) into the sulfur dioxide absorption module (2) and used again to absorb sulfur dioxide gas in the boiler flue gas. The hydrogen discharged from the hydrogen separation module (8) enters the hydrogen storage module (9) for storage. The hydrogen fuel cell module (10) consumes hydrogen discharged from the hydrogen storage module (9) to generate electricity, and the electrical energy generated by the hydrogen fuel cell module (10) enters the power grid through the power transmission module (12).

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