A small sulphuric acid plant

Abstract

The utility model relates to a kind of small sulphur sulphuric acid plant, comprising: first molten sulphur module, second molten sulphur module, liquid sulphur filtering module, liquid sulphur underground tank module, burning sulphur module, waste heat recovery module, first heat exchanger module, second heat exchanger module, third heat exchanger module and converter module, first dry absorption module, second dry absorption module, third dry absorption module, fourth dry absorption module, fifth dry absorption module, sixth dry absorption module, seventh dry absorption module, eighth dry absorption module, and fan module, first tail gas absorption module, second tail gas absorption module, third tail gas absorption module and fourth tail gas absorption module. Thus, it can be completed in the factory, and then transported to the project site for installation, not only can effectively compress land demand, enhance the flexibility of deployment, solve the problem of the scale of traditional equipment limitation and flexibility shortage, but also, it can shorten construction period, provide efficiency.

Description

Technical Field

[0001] This utility model relates to a chemical equipment, and more particularly to a sulfuric acid production equipment suitable for small-scale production, specifically a small-scale sulfuric acid production equipment. Background Technology

[0002] Sulfur-based sulfuric acid production is currently the most common process for sulfuric acid production globally. According to the International Fertilizer Industry Association (IFA), approximately 65-70% of global sulfuric acid production comes from sulfur combustion processes. In some regions or countries, end-users of sulfuric acid, such as fertilizer plants, metal smelters, and chemical enterprises, may be geographically dispersed, and the demand from each user or local area may be insufficient to support the economic operation of a large-scale plant with an annual capacity of millions of tons. Therefore, the construction of small-scale sulfuric acid production plants is receiving increasing attention.

[0003] Currently, most existing sulfuric acid production plants are non-standard designs. Moreover, the equipment needs to be distributed and the safety spacing is redundant, resulting in a large footprint and long construction period, which increases construction costs and makes it difficult to meet market demand.

[0004] Therefore, improvements are urgently needed to better meet market demands. Utility Model Content

[0005] The purpose of this invention is to address the problems encountered in the current field of small-scale sulfuric acid production by providing a small-scale sulfuric acid production unit. Through modular design, it effectively reduces land requirements and enhances deployment flexibility, solving the problems of scale limitations and insufficient flexibility of traditional equipment. Furthermore, it can be manufactured in a factory and then transported to the project site for installation, greatly shortening the construction period and improving production efficiency.

[0006] The technical solution of this utility model is: A small-scale sulfuric acid production unit includes the following functional modules that can be prefabricated in a factory and assembled on-site: The first sulfur melting module is equipped with a rapid sulfur melting tank. The second sulfur melting module is equipped with a filter aid tank, a filter tank, and a refined sulfur tank. Liquid sulfur underground tank module; This liquid sulfur underground tank module is equipped with a refined sulfur tank; Sulfur incineration module; This sulfur incineration module is equipped with one sulfur incineration furnace; First heat exchanger module; This first heat exchanger module is equipped with two electric heaters for use during the start-up process; The second heat exchanger module includes a high-temperature superheater, a low-temperature superheater, economizer II, and economizer I. The third heat exchanger module is equipped with a heat exchanger and a cold exchanger. Converter module; This converter module is equipped with a reactor to convert SO2 into SO3 under the catalytic action of a catalyst; The unit comprises a lower drying absorption module and an upper drying absorption module. The lower drying absorption module is equipped with an acid circulation tank, an acid circulation pump, and an acid cooler. The upper drying absorption module is equipped with an absorption tower. There are multiple lower and upper drying absorption modules, which are connected to each other in a one-to-one correspondence to form a drying absorption module with an upper and lower structure. First tail gas absorption module; the first tail gas absorption module is equipped with a sodium carbonate solution preparation tank and a sodium carbonate solution delivery pump; Second exhaust gas absorption module; the second exhaust gas absorption module is equipped with an exhaust gas absorption tower and a circulation pump; The third tail gas absorption module is equipped with a sodium carbonate solution buffer tank, a sodium hydroxide solution preparation tank, a sodium carbonate solution pump, and a sodium hydroxide solution delivery pump. The fourth tail gas absorption module is equipped with a sodium hydroxide solution buffer tank, a sodium hydroxide solution pump, a sodium sulfite solution crystallization tank, and a sodium sulfite delivery pump. The outlet of the rapid sulfur melting tank is connected to the filter aid tank via a pipeline; the outlet of the refined sulfur tank passes through the refined sulfur storage tank and the underground liquid sulfur tank module in sequence before being connected to the sulfur combustion module; the sulfur combustion module passes through the waste heat recovery module, the first heat exchanger module (only passed through during start-up, not during production), the converter module, the second heat exchanger module, and the third heat exchanger module in sequence before being connected to the drying absorption module, and then passes through the first tail gas absorption module, the second tail gas absorption module, the third tail gas absorption module, and the fourth tail gas absorption module before being connected to the outside of the boundary area.

[0007] Furthermore, it also includes a waste heat recovery module; this waste heat recovery module is equipped with a waste heat boiler; the outlet of the waste heat boiler is connected to the inlet of the electric heater I in the first heat exchanger module (only during startup) or to the inlet of the first bed layer of the converter module (during production), and its inlet is connected to the outlet of the sulfur incinerator. Furthermore, the filter aid tank is equipped with a filter aid pump; the filter tank is equipped with a filter pump; and the sulfur purification tank is equipped with a sulfur purification pump; the filter aid tank, filter tank, and sulfur purification tank are designed as a three-in-one unit.

[0008] Furthermore, it also includes a liquid sulfur filtration module; the liquid sulfur filtration module includes a liquid sulfur filter and is connected to the outlet of the filter aid tank, the outlet of the filter tank and the inlet of the refined sulfur tank respectively.

[0009] Furthermore, the lower drying absorption module includes: a first drying absorption module, a second drying absorption module, a third drying absorption module, and a fourth drying absorption module; the upper drying absorption module includes: a fifth drying absorption module, a sixth drying absorption module, a seventh drying absorption module, and an eighth drying absorption module; it also includes a fan module; the fan module is equipped with an air fan and a boiler feed water pump, and is located close to the drying absorption tower in the eighth drying absorption module in order to reduce pressure drop.

[0010] Furthermore, the acid outlets at the bottom of the fifth, sixth, seventh, and eighth drying absorption modules are respectively connected to the acid tank inlets of the first, second, third, and fourth drying absorption modules, respectively. The circulating liquid inlets at the top of the fifth, sixth, seventh, and eighth drying absorption modules are respectively connected to the acid cooler outlets of the first, second, third, and fourth drying absorption modules.

[0011] Furthermore, the first exhaust gas absorption module is arranged close to the first drying absorption module, and the two are located on the same installation horizontal line; the second exhaust gas absorption module is arranged above the first exhaust gas absorption module; the third and fourth exhaust gas absorption modules are arranged side by side to the right of the first exhaust gas absorption module.

[0012] The beneficial effects of this utility model are: This utility model has a reasonable design, simple structure, and is easy to use. It can be manufactured in the factory and then transported to the project site for installation. This can effectively reduce land use requirements and enhance deployment flexibility, solving the problems of scale limitations and insufficient flexibility of traditional equipment. In addition, it can shorten the construction period, improve production efficiency, and fully meet market demands. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of this device.

[0014] Among them, 1-first sulfur melting module, 2-second sulfur melting module, 3-liquid sulfur filtration module, 4-liquid sulfur underground tank module, 5-refined sulfur storage tank, 6-sulfur incineration module, 7-waste heat recovery module, 8-second heat exchanger module, 9-converter module, 10-third heat exchanger module, 12-fan module, 13-eighth drying absorption module, 14-fourth drying absorption module, 15-seventh drying absorption module, 16-third drying absorption module, 17-sixth drying absorption module, 18-second drying absorption module, 19-fifth drying absorption module, 20-first drying absorption module, 24-second tail gas absorption module, 25-first tail gas absorption module, 26-third tail gas absorption module, 27-fourth tail gas absorption module, 28-first heat exchanger module. Detailed Implementation

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0016] like Figure 1 As shown, A small-scale sulfuric acid production device includes the following functional modules: The system includes: a first sulfur melting module 1, a second sulfur melting module 2, a liquid sulfur filtration module 3, a liquid sulfur underground tank module 4, a sulfur incineration module 6, a waste heat recovery module 7, a first heat exchanger module 28, a second heat exchanger module 8, a third heat exchanger module 10, a converter module 9, a first drying and absorption module 20, a second drying and absorption module 18, a third drying and absorption module 16, a fourth drying and absorption module 14, a fifth drying and absorption module 19, a sixth drying and absorption module 17, a seventh drying and absorption module 15, an eighth drying and absorption module 13, a fan module 12, a first tail gas absorption module 25, a second tail gas absorption module 24, a third tail gas absorption module 26, and a fourth tail gas absorption module 27.

[0017] The first sulfur melting module 1 is equipped with a rapid sulfur melting tank, and the outlet of the rapid sulfur melting tank is connected to the filter aid tank 21 in the second sulfur melting module 2 through a pipeline.

[0018] The second sulfur melting module 2 is equipped with a filter aid tank 21 and a filter aid pump within the tank, a filter tank 22 and a filter pump within the tank, and a refined sulfur tank 23 and a refined sulfur pump within the tank. The filter aid tank 21, filter tank 22, and refined sulfur tank 23 are designed as a single unit. The outlet of the filter aid tank 21, the outlet of the filter tank 22, and the inlet of the refined sulfur tank 23 in the second sulfur melting module 2 are all connected to the liquid sulfur filter in the liquid sulfur filter module 3 via pipelines. The outlet of the refined sulfur tank 23 is connected to the refined sulfur storage tank 5.

[0019] The liquid sulfur filtration module 3 and the second sulfur melting module 2 have a positional difference, mainly to match the elevation of the downstream storage tank or conveying pipeline, forming a gravity-flow process and preventing the liquid sulfur from solidifying due to stagnation. Typically, the liquid sulfur filtration module is arranged at a relatively high height. Each liquid sulfur filtration module is equipped with one liquid sulfur filter.

[0020] The underground liquid sulfur tank module 4 is equipped with a refined sulfur tank and a refined sulfur pump located within the tank, serving as a maintenance and backup tank for the refined sulfur storage tank 5. The inlet of the underground liquid sulfur tank module 4 is connected to the outlet of the refined sulfur storage tank 5 via a pipeline, and its outlet is connected to the sulfur combustion furnace within the sulfur combustion module 6 via a pipeline.

[0021] The first sulfur melting module 1, the second sulfur melting module 2, the liquid sulfur filtration module 3, and the liquid sulfur underground tank module 4 constitute a sulfur melting unit to realize the melting, filtration, and transportation of sulfur.

[0022] The sulfur incineration module 6 is equipped with a sulfur incineration furnace and is arranged close to the waste heat recovery module 7. The waste heat recovery module 7 is equipped with a waste heat boiler, whose flue gas inlet and sulfur incineration furnace outlet are at the same height and connected by pipelines. This shortens the connecting pipelines between the equipment, effectively reduces pressure drop, allows high-temperature gas to directly enter the boiler, and reduces heat loss.

[0023] The first heat exchanger module 28 is equipped with electric heater I and electric heater II for use during operation. The inlet of electric heater I is connected to the waste heat boiler outlet of the waste heat recovery module 7.

[0024] The second heat exchanger module 8 is equipped with a high-temperature superheater, a low-temperature superheater, an economizer II, and an economizer I, which can recover the heat from the sulfur incinerator and the conversion reaction, so that the gas temperature is controlled within the specified range of each conversion stage, and at the same time produce qualified steam.

[0025] The third heat exchanger module 10 is equipped with a heat exchanger and a cold exchanger to recover the heat from the conversion reaction.

[0026] The first, second, and third heat exchanger modules centrally arrange the heat exchangers, effectively reducing the equipment's footprint. Simultaneously, the heat exchanger modules are positioned close to the converter module, effectively minimizing heat transfer distance and heat loss.

[0027] The converter module 9 is equipped with a reactor that converts SO2 into SO3 under the catalysis of a catalyst. This reactor has four bed sections and employs a two-conversion, two-absorption process. During startup, the inlet of the first bed section is connected to the outlet of electric heater I via a pipeline. During normal production, the inlet of the first bed section is connected to the outlet of the waste heat boiler via a pipeline, and the outlet of the first bed section is connected to the high-temperature superheater via a pipeline. The inlet of the second bed section is connected to the outlet of the high-temperature superheater via a pipeline, and the outlet of the second bed section is connected to the inlet of the heat exchanger in heat exchange module 3 10 via a pipeline. The inlet of the third bed section is connected to the outlet of the heat exchanger in heat exchange module 3 10 via a pipeline. The outlet of the third bed section is connected to the inlet of the cold exchanger in heat exchange module 3 10 via a pipeline. During startup, the inlet of the fourth bed section is connected to the outlet of electric heater II via a pipeline. During normal production, the inlet of the fourth bed section is connected to the outlet of the heat exchanger via a pipeline, and the outlet of the fourth bed section is connected to the inlet of the low-temperature superheater via a pipeline.

[0028] The sulfur combustion module 6, waste heat recovery module 7, first heat exchanger module 28, second heat exchanger module 8, third heat exchanger module 10 and converter module 9 constitute a sulfur combustion conversion unit to complete sulfur combustion, SO2 conversion and heat recovery.

[0029] The first drying absorption module 20, the second drying absorption module 18, the third drying absorption module 16, and the fourth drying absorption module 14 are each equipped with an acid circulation tank, an acid circulation pump, an acid cooler, and corresponding pipelines, and the above four drying absorption modules are located on the same installation horizontal plane.

[0030] Each of the fifth drying absorption module 19, the sixth drying absorption module 17, the seventh drying absorption module 15, and the eighth drying absorption module 13 is equipped with an absorption tower, which is arranged above the first drying absorption module 20, the second drying absorption module 18, the third drying absorption module 16, and the fourth drying absorption module 14, respectively. They are connected by detachable steel columns to form four drying absorption modules, which facilitates on-site construction.

[0031] Furthermore, the inlet of the flue gas from the second absorption tower in the fifth drying absorption module 19 is connected to the outlet of the economizer I in the second heat exchanger module 8 via a pipeline, and its outlet is connected to the inlet of the flue gas from the tail absorption tower in the second tail gas absorption module 24.

[0032] Furthermore, the inlet of the flue gas at the bottom of the absorption tower in the sixth drying absorption module 17 is connected to the flue gas outlet of the nicotinic acid tower in the seventh absorption module 15 via a pipeline. Simultaneously, the flue gas outlet at the top of the absorption tower is connected to the inlet of the cold exchanger 102 in the third heat exchanger module 10 via a pipeline.

[0033] Furthermore, the flue gas inlet at the bottom of the absorption tower in the seventh drying absorption module 15 is connected to the economizer II outlet in the second heat exchanger module 8, and fumed sulfuric acid is produced at the bottom of the absorption tower.

[0034] Furthermore, the air outlet at the top of the eighth absorption module 13 is connected to the air inlet of the sulfur incineration furnace in the sulfur incineration module 6, and the sulfuric acid outlet at the bottom of the module is connected to the acid tank in the fourth drying absorption module 14.

[0035] The acid outlets at the bottom of the fifth, sixth, seventh, and eighth drying and absorption modules are connected to the acid tank inlets of the first, second, third, and fourth drying and absorption modules, respectively. The circulating liquid inlets at the top of the fifth, sixth, seventh, and eighth drying and absorption modules are connected to the acid cooler outlets of the first, second, third, and fourth drying and absorption modules, respectively.

[0036] The aforementioned fan module includes an air fan and a boiler feedwater pump. The fan is located near the eighth drying and absorption module 13, and its outlet is connected to the air inlet of the absorption tower within the eighth drying and absorption module 13 to reduce pressure drop. The boiler feedwater pump inlet is connected to the deaerator within the deaerator module 11, and the boiler feedwater pump outlet is connected to the economizer II 84 within the second heat exchange module 8.

[0037] The first tail gas absorption module 25 is equipped with a sodium carbonate solution preparation tank and a sodium carbonate solution delivery pump.

[0038] The second exhaust gas absorption module 24 is equipped with an exhaust gas absorption tower and a circulation pump.

[0039] The third tail gas absorption module 26 is equipped with a sodium carbonate solution buffer tank, a sodium hydroxide solution preparation tank, a sodium carbonate solution pump, and a sodium hydroxide solution delivery pump.

[0040] The fourth tail gas absorption module 27 is equipped with a sodium hydroxide solution buffer tank, a sodium hydroxide solution pump, a sodium sulfite solution crystallization tank, and a sodium sulfite delivery pump.

[0041] The first exhaust gas absorption module 25 is arranged close to the first drying absorption module 20, and both are on the same installation horizontal line. The second exhaust gas absorption module 24 is arranged above the first exhaust gas absorption module 25. The third exhaust gas absorption module 26 and the fourth exhaust gas absorption module 27 are arranged side by side to the right of the first exhaust gas absorption module.

[0042] Preferably, the first tail gas absorption module 25 is connected to the sodium carbonate solution buffer tank in the third tail gas absorption module 26. A sodium carbonate solution inlet is located at the bottom of the tail gas absorption tower in the second tail gas absorption module 24, and is connected to the sodium carbonate solution pump outlet in the third tail gas absorption module 26. A circulation pump in the second tail gas absorption module 24 is located next to the tail gas absorption tower. The outlet of this circulation pump is connected to the sodium sulfite solution storage tank in the fourth tail gas absorption module 27. The inlet of the sodium hydroxide solution buffer tank in the fourth tail gas absorption module 27 is connected to the outlet of the sodium hydroxide solution delivery pump in the third tail gas absorption module.

[0043] The functional modules are connected by standardized pipes, valves, etc., for easy operation.

[0044] The equipment installed in each functional module is a conventional device in the field, and related modular steel structures are designed to connect these devices. Specifically: horizontal equipment is equipped with a saddle, which is bolted to the equipment, such as liquid sulfur filters, sulfur incinerators, waste heat boilers, acid circulation tanks, acid coolers, and deaerators. Vertical equipment has supporting steel beams at the bottom of the module structure. These beams are matched with pre-drilled bolt holes in the equipment skirts or supports, and are also bolted together, such as tower equipment, heat exchangers, cold exchangers, economizers, solution preparation tanks, and solution buffer tanks. During the modular structure design, supplementary calculations and designs were performed for module hoisting and transportation. Necessary anti-sway support points were added between the module structure and the equipment to provide additional lateral support during hoisting and transportation, improving the overall stability of the module.

[0045] The operation process of this utility model is as follows: 1. Construction process: During startup, the sulfur melting unit, sulfur combustion unit, and waste heat recovery process are all the same as normal production processes. After recovering heat energy in the waste heat recovery module 7, the gas enters the first heat exchanger module 8 and is heated to 420°C by electric heater I. The first conversion and absorption are the same as normal production processes. After the acid mist is removed by the fiber demister in the sixth drying and absorption module 17, the gas passes through the third heat exchanger module 10 in sequence, where it undergoes countercurrent heat exchange with the furnace gas from the third and second stage outlets of the converter module 9. The gas is heated to 420°C by electric heater II and then enters the fourth stage catalyst bed of the converter module 9 for conversion. The subsequent second absorption process and tail gas treatment process are the same as normal production processes.

[0046] In this process, by controlling the number of electric heater power supply groups, the inlet temperature of the first and fourth stages of the converter is kept at around 420°C. The amount of sulfur added is gradually increased, and the self-heating balance of the conversion unit is gradually reached. The number of electric heater power supply groups is reduced until they are all shut down. The bypass valve is opened and the electric heater valve is closed. The process flow is as described in the normal production process.

[0047] 2. Normal production process: Solid sulfur is melted sequentially in the first sulfur melting module 1, preliminarily purified in the second sulfur melting module 2, and deeply filtered in the liquid sulfur filtration module 3. It is then temporarily stored in the refined sulfur storage tank 5 and the underground liquid sulfur tank module 4. The purified liquid sulfur is pumped into the sulfur combustion module 6 to generate high-temperature SO2 gas, which enters the waste heat recovery module 7 to recover heat energy. After the temperature drops to 452℃, it enters the first catalyst bed of the converter module 9. After reaction, the temperature rises to approximately 598℃ and enters the second heat exchanger module 8 for heat exchange. The temperature drops to approximately 450℃ and enters the second catalyst bed of the converter module 9 for catalytic reaction. The temperature rises to approximately 510℃, and then exits the converter module 9 into the third heat exchanger module 10 to cool to 440℃ before entering the third catalyst bed of the converter module 9 for further reaction. The gas exiting the third stage of the converter sequentially enters the third heat exchanger module 10 and the second heat exchanger module 8 to recover heat and lower the temperature to 180℃. At this point, the furnace gas has completed its first conversion and sequentially enters the seventh drying and absorption module 15 and the sixth drying and absorption module 17. In the seventh drying and absorption module 15 and the sixth drying and absorption module 17, SO3 in the gas is absorbed by 105.4% fuming acid and 98% sulfuric acid, respectively. After the SO3 is absorbed, the fuming acid and concentrated sulfuric acid, with increased concentrations, flow into the third drying and absorption module 16 and the second drying and absorption module 18, respectively. They are then pumped to the top of the tower. The gas then passes through the fiber demister in the sixth drying and absorption module 17 to remove the acid mist. After passing through the third heat exchanger module 10, the gas undergoes countercurrent heat exchange with the furnace gas from the third and second stage outlets of the converter module 9. The gas is heated to 430°C and then enters the catalyst bed in the fourth stage of the converter module 9 for conversion. The gas exiting the fourth bed layer recovers heat through the second heat exchange module 8, reducing its temperature to 160℃. At this point, the furnace gas completes its second transformation and enters the fifth drying and absorption module 19. In the fifth drying and absorption module 19, SO3 is absorbed by 98% sulfuric acid and then passes through a fiber demister at the top of the tower to remove acid mist. The tail gas exiting the fifth drying and absorption module 19 is processed with Na2CO3 solution in the second tail gas absorption module 24 and then sequentially transported to the third tail gas absorption module 26 and the second tail gas absorption module 24 for absorption before being discharged through the chimney. The concentrated sulfuric acid, whose concentration increases after SO3 absorption in the fifth drying and absorption module 19, flows into the first drying and absorption module 20 and is then circulated back to the top of the tower by a pump. The sodium bisulfite-containing solution generated after SO2 is absorbed by the second tail gas absorption module 24 is pumped to the fourth tail gas absorption module 27. The NaOH solution prepared by the third tail gas absorption module 26 is transported to the fourth tail gas absorption module 27. After neutralizing with the sodium bisulfite-containing solution to pH 7.5~8.5, it is transported outside the boundary for use.

[0048] This utility model adopts a modular design, which can be manufactured in the factory and then transported to the project site for installation. This can effectively reduce land use requirements and enhance deployment flexibility, solving the problems of scale limitations and insufficient flexibility of traditional equipment. In addition, it can also shorten the construction period, improve production efficiency, and fully meet market demands.

[0049] The parts not covered in this utility model are the same as or can be implemented using existing technologies.

Claims

1. A small-scale sulfuric acid production device, characterized in that, This includes the following functional modules that can be prefabricated in the factory and assembled on the construction site: The first sulfur melting module is equipped with a rapid sulfur melting tank. The second sulfur melting module is equipped with a filter aid tank, a filter tank, and a refined sulfur tank. Liquid sulfur underground tank module; This liquid sulfur underground tank module is equipped with a refined sulfur tank; Sulfur incineration module; This sulfur incineration module is equipped with one sulfur incineration furnace; First heat exchanger module; This first heat exchanger module is equipped with two electric heaters for use during the start-up process; The second heat exchanger module includes a high-temperature superheater, a low-temperature superheater, economizer II, and economizer I. The third heat exchanger module is equipped with a heat exchanger and a cold exchanger. Converter module; This converter module is equipped with a reactor to convert SO2 into SO3 under the catalytic action of a catalyst; The unit comprises a lower drying absorption module and an upper drying absorption module. The lower drying absorption module is equipped with an acid circulation tank, an acid circulation pump, and an acid cooler. The upper drying absorption module is equipped with an absorption tower. There are multiple lower and upper drying absorption modules, which are connected to each other in a one-to-one correspondence to form a drying absorption module with an upper and lower structure. First tail gas absorption module; the first tail gas absorption module is equipped with a sodium carbonate solution preparation tank and a sodium carbonate solution delivery pump; Second exhaust gas absorption module; the second exhaust gas absorption module is equipped with an exhaust gas absorption tower and a circulation pump; The third tail gas absorption module is equipped with a sodium carbonate solution buffer tank, a sodium hydroxide solution preparation tank, a sodium carbonate solution pump, and a sodium hydroxide solution delivery pump. The fourth tail gas absorption module is equipped with a sodium hydroxide solution buffer tank, a sodium hydroxide solution pump, a sodium sulfite solution crystallization tank, and a sodium sulfite delivery pump. The outlet of the rapid sulfur melting tank is connected to the filter aid tank via a pipeline; the outlet of the refined sulfur tank passes through the refined sulfur storage tank and the underground liquid sulfur tank module in sequence before being connected to the sulfur combustion module; the sulfur combustion module passes through the first heat exchanger module (only during startup, not during production), the converter module, the second heat exchanger module, and the third heat exchanger module in sequence before being connected to the drying absorption module, and then passes through the first tail gas absorption module, the second tail gas absorption module, the third tail gas absorption module, and the fourth tail gas absorption module before being connected to the outside of the boundary area.

2. The small-scale sulfuric acid production device according to claim 1, characterized in that, It also includes a waste heat recovery module; the waste heat recovery module is equipped with a waste heat boiler; the outlet of the waste heat boiler is connected to the inlet of the electric heater I in the first heat exchanger module (only during start-up) or to the inlet of the first bed layer of the converter module (during production), and its inlet is connected to the outlet of the sulfur incinerator.

3. The small-scale sulfuric acid production device according to claim 1, characterized in that, The filter aid tank is equipped with a filter aid pump; the filter tank is equipped with a filter pump; the sulfur purification tank is equipped with a sulfur purification pump; the filter aid tank, filter tank and sulfur purification tank are designed as a three-in-one unit.

4. The small-scale sulfuric acid production device according to claim 1, characterized in that, It also includes a liquid sulfur filtration module; the liquid sulfur filtration module contains a liquid sulfur filter and is connected to the outlet of the filter aid tank, the outlet of the filter tank and the inlet of the refined sulfur tank respectively.

5. The small-scale sulfuric acid production device according to claim 1, characterized in that, The lower drying absorption module includes: a first drying absorption module, a second drying absorption module, a third drying absorption module, and a fourth drying absorption module; the upper drying absorption module includes: a fifth drying absorption module, a sixth drying absorption module, a seventh drying absorption module, and an eighth drying absorption module; it also includes a fan module; the fan module is equipped with an air fan and a boiler feed water pump, and is located close to the drying absorption tower in the eighth drying absorption module in order to reduce pressure drop.

6. The small-scale sulfuric acid production device according to claim 5, characterized in that, The acid outlets at the bottom of the fifth, sixth, seventh, and eighth drying absorption modules are connected to the acid tank inlets of the first, second, third, and fourth drying absorption modules, respectively. The circulating liquid inlets at the top of the fifth, sixth, seventh, and eighth drying absorption modules are connected to the acid cooler outlets of the first, second, third, and fourth drying absorption modules, respectively.

7. The small-scale sulfuric acid production device according to claim 5, characterized in that, The first exhaust gas absorption module is arranged close to the first drying absorption module, and the two are located on the same installation horizontal line; the second exhaust gas absorption module is arranged above the first exhaust gas absorption module; the third and fourth exhaust gas absorption modules are arranged side by side to the right of the first exhaust gas absorption module.

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