Method and system for regenerating inactivated demercuration adsorbent through light-heat coupling strong jet flow

Abstract

The invention provides a method and a system for regenerating an inactivated mercury removal adsorbent through light-heat coupling strong jet flow. The system mainly comprises an opposite-phase impact regeneration device, a high-speed nozzle arranged in the opposite-phase impact regeneration device, an ultraviolet lamp tube, a material mixing preheating tower, a stirrer, a flue gas waste heat exchanger, a liquid-solid separator and a flue gas-air heat drying and activating system. High-activity free radicals are induced by utilizing ultraviolet light-flue gas waste heat and a counter-impact flow coupling activation regeneration reagent in an opposite-phase counter-impact regeneration device, and the high-activity free radicals can generate a violent chemical reaction with harmful substances covering surface sites of an inactivated adsorbent; and the high-speed jet flow generated by the counter-impact flow can impact covering substances on the surface and in gaps of the adsorbent, so that the deactivated mercury removal adsorbent is regenerated synergistically from two aspects of chemistry and physics. The device disclosed by the invention has the comprehensive advantages of simple structure, high regeneration efficiency, high mass transfer and diffusion efficiency, energy conservation, low carbon, green and environment-friendly operation process and the like, and has good industrial application value.

Description

Technical Field

[0001] This invention belongs to the field of air pollution control, specifically relating to a method and system for regenerating deactivated mercury adsorbents using a photo-thermal coupled strong jet. Background Technology

[0002] Mercury, a heavy metal emitted from coal-fired boilers and waste incinerators, can cause serious health problems such as cancer and birth defects. To control the excessive emission of this harmful pollutant, mercury, environmental scientists both domestically and internationally have developed numerous flue gas mercury removal technologies, including selective catalytic reduction (SCR) synergistic mercury removal, catalytic mercury removal, adsorption mercury removal, traditional oxidative mercury removal, and free radical advanced oxidative mercury removal. Among these technologies, adsorption mercury removal boasts advantages such as high removal efficiency, mature and reliable technology, and environmentally friendly processes. Its representative activated carbon injection adsorption mercury removal technology has already been applied in various industries. However, the main challenge in applying adsorption mercury removal technology is its high operating cost. This is primarily because common carbon-based adsorbents are susceptible to poisoning and deactivation by impurities such as sulfur, water, alkali metals, and heavy metals in coal-fired flue gas, resulting in a short lifespan for the adsorbent and significantly increasing the operating cost. To reduce the operating costs of mercury removal adsorbents, researching and developing efficient, environmentally friendly, and economical regeneration technologies for mercury removal adsorbents has significant theoretical and engineering value. This can not only reduce the application costs of mercury removal adsorption technology, but also effectively alleviate the challenges of subsequent treatment of heavy metal-containing solid waste caused by deactivated mercury removal adsorbents.

[0003] Researchers in this field have developed various regeneration methods for carbon-based mercury removal adsorbents, mainly including thermal regeneration, microwave regeneration, water washing regeneration, acid washing regeneration, alkaline washing regeneration, ultrasonic regeneration, traditional oxidant regeneration, and plasma regeneration. Thermal and microwave regeneration technologies can achieve certain regeneration effects, but they consume a lot of energy and easily damage the pore structure of the adsorbent. Water washing regeneration can remove some loose harmful substances, but it is difficult to remove most stubborn harmful substances. Acid and alkaline washing regeneration technologies can remove most harmful substances and have good regeneration effects, but strong acids and alkalis are highly corrosive to the adsorbent and easily damage the pore structure. Regeneration using traditional oxidants such as potassium permanganate and sodium chlorite can achieve high regeneration effects, but they are expensive. Oxidation regeneration using traditional oxidants such as persulfate and hydrogen peroxide has advantages such as low cost and environmental friendliness, but unactivated peroxides have very low oxidation performance, making it difficult to achieve good regeneration results. Furthermore, acid / alkali activation regeneration and regeneration with traditional oxidants (such as potassium permanganate and sodium chlorite) generate wastewater and waste liquid, leading to new secondary pollution problems. Plasma regeneration has good regeneration efficiency, but plasma technology has drawbacks such as high energy consumption and low reliability of key devices. Moreover, the extreme environment induced by plasma can easily damage the surface and pore structure of the adsorbent. Ultrasonic regeneration technology has low regeneration efficiency when used alone and is usually used as an auxiliary method in combination with other regeneration technologies.

[0004] In summary, although numerous adsorbent regeneration technologies have been developed, these technologies generally suffer from drawbacks such as low regeneration efficiency, high energy consumption, complex equipment, low reliability, high operating costs, or secondary pollution, hindering their widespread application. Therefore, it is necessary to actively develop a regeneration method and system for carbon-based adsorbents that features high regeneration efficiency, simple equipment, low cost, low energy consumption, high reliability, and environmentally friendly operation. Summary of the Invention

[0005] To address the aforementioned challenges and bottlenecks, this invention provides a method and system for regenerating deactivated mercury-removing adsorbents using a photo-thermal coupled high-pressure jet. In a counter-current regeneration device, ultraviolet light and waste heat from flue gas are coupled with a counter-current to activate a regeneration reagent, inducing the regeneration of highly reactive free radicals. These highly reactive free radicals can undergo vigorous chemical reactions with harmful substances covering the surface sites of the deactivated adsorbent, while the high-speed jet generated by the counter-current impacts the covering material on the adsorbent surface and in the pores. The two processes synergistically regenerate the deactivated mercury-removing adsorbent from both chemical and physical perspectives. The method and apparatus for regenerating deactivated mercury-removing adsorbents provided by this invention offer comprehensive advantages, including simple technology, high regeneration efficiency, high mass transfer and diffusion efficiency, energy saving and low carbon emissions, and green and environmentally friendly operation, making it highly valuable for industrial applications.

[0006] This invention provides a system for regenerating deactivated mercury adsorbents using a photo-thermal coupled strong jet, characterized in that it mainly includes an opposite-phase impact regeneration device for regenerating the deactivated mercury adsorbent; multiple high-speed nozzles placed on the inner wall of the opposite-phase impact regeneration device for spraying liquid-solid mixed media; an ultraviolet lamp placed inside the opposite-phase impact regeneration device for radiative decomposition of the regeneration reagent to induce free radicals; a material mixing preheating tower connected to the lower part of the opposite-phase impact regeneration device for mixing and preheating liquid and solid materials; a stirrer placed inside the material mixing preheating tower for stirring the liquid and solid materials to achieve uniform mixing; a flue gas waste heat exchanger for heating the material temperature using flue gas waste heat; a liquid-solid separator connected to the bottom of the opposite-phase impact regeneration device for rapidly separating the residual liquid and adsorbent after regeneration; and a flue gas-air thermal drying and activation system connected to the liquid-solid separator for drying and activating the adsorbent using flue gas waste heat.

[0007] The material mixing and preheating tower is provided with a regeneration reagent inlet a and a deactivated mercury adsorbent inlet b on the upper two sides, and a mixed material outlet c and d on the left and right sides respectively, which are connected to high-speed nozzles to form a medium transport and spraying system.

[0008] The flue gas-air thermal drying and activation system is equipped with a thermosiphon pipe for utilizing the waste heat of the flue gas.

[0009] Furthermore, the aforementioned impact regeneration device is a rectangular reactor with a cover plate on top and a regenerated material outlet e at the bottom connected to a liquid-solid separator.

[0010] Furthermore, a first circulation pump and a second circulation pump are respectively installed on the pipelines between the mixture outlets c and d of the material mixing preheating tower and the high-speed nozzle.

[0011] Furthermore, the liquid-solid separator has a residual liquid discharge port f below it and an adsorbent outlet g on its side connected to the flue gas-air thermal drying and activation system; the flue gas-air thermal drying and activation system has a dried and activated adsorbent outlet h below it.

[0012] Furthermore, in the aforementioned impact regeneration device, the high-speed nozzles are arranged at equal intervals in both the longitudinal and transverse directions, with the effective length range between the intervals A being 30 cm to 120 cm; the high-speed nozzles arranged on both sides of the impact regeneration device are arranged coaxially opposite each other, and the effective range of the horizontal distance L between two coaxially opposite nozzles is 40 cm to 200 cm.

[0013] Furthermore, the ultraviolet lamps are arranged at the diagonal center of the four adjacent high-speed nozzles and are set horizontally to obtain the maximum radiation range.

[0014] Furthermore, in the aforementioned impact regeneration device, the effective ultraviolet radiation intensity range of the ultraviolet lamp is 5 μW / cm². 2 ~ 300 μW / cm 2 The effective range of the ultraviolet lamp emission wavelength is between 180 nm and 280 nm.

[0015] Furthermore, the regeneration reagent is composed of a mixture of sodium persulfate and hydrogen peroxide, with the concentration of sodium persulfate ranging from 0 mol / L to 3.2 mol / L and the concentration of hydrogen peroxide ranging from 0 mol / L to 2.8 mol / L; the pH value of the regeneration reagent ranges from 0.01 to 8.5; the effective operating temperature of the regeneration device is between 15℃ and 70℃; and the effective operating temperature of the flue gas-air thermal drying and activation system is between 60℃ and 350℃.

[0016] Furthermore, the deactivated mercury removal adsorbent includes one or more carbon-based adsorbents such as porous carbon, biochar, and petroleum coke.

[0017] The method for regenerating and deactivating mercury-removing adsorbents based on the aforementioned photo-thermal coupled strong jet method of the regenerated and deactivated mercury-removing adsorbent system is characterized by comprising the following steps:

[0018] S1. After the peroxide regeneration reagent sodium persulfate and hydrogen peroxide are mixed evenly, they are fed into the material mixing preheating tower through the regeneration reagent inlet a. The deactivated mercury removal adsorbent is fed into the material mixing preheating tower through the deactivated mercury removal adsorbent inlet b. The agitator and flue gas waste heat exchanger are started simultaneously to mix and heat the mixing medium of the two materials.

[0019] S2. The uniformly mixed and preheated medium is injected at high speed into the reaction zone of the adsorption regeneration device through high-speed nozzles via the first and second circulation pumps. Simultaneously, the ultraviolet lamps are activated to emit ultraviolet light, which, together with the waste heat of the flue gas, decomposes the peroxide regeneration reagent, inducing the generation of hydroxyl radicals, sulfate radicals, and superoxide radicals. The free radicals attack the covering material on the active sites of the deactivated adsorbent surface. At the same time, the ultra-strong micro-jet induced by the adsorption flow impacts the residual material on the adsorbent after being attacked by free radicals, thus removing the covering material on the adsorbent surface from both chemical and physical aspects, thereby achieving the regeneration of the adsorbent.

[0020] S3. The mixture of residual liquid and impurities after regeneration enters the liquid-solid separator from the regenerated material outlet e for liquid-solid separation; the separated residual liquid is recycled and reused through the residual liquid discharge outlet f; the separated solid adsorbent enters the flue gas-air thermal drying and activation system from the adsorbent outlet g for drying and activation; the heat energy required for drying and activation is heated by the waste heat of the flue gas through the thermosiphon; the dried and activated adsorbent is recycled and reused through the adsorbent outlet h.

[0021] The basic principle of the method and system described in this invention is as follows: In the opposite-opposition regeneration device, ultraviolet light-flue gas waste heat and the opposing flow are coupled to activate the regeneration reagent to induce highly active free radicals to regenerate and activate the deactivated mercury removal adsorbent. The highly active free radicals can undergo violent chemical reactions with the harmful substances covering the sites on the surface of the deactivated adsorbent, while the high-speed jet generated by the opposing flow can impact the covering material on the surface and pores of the adsorbent. The two work together to regenerate the deactivated mercury removal adsorbent from both chemical and physical perspectives. The regenerated adsorbent can be dried and activated using the flue gas waste heat to obtain higher adsorption and mercury removal performance. The above-mentioned adsorbent regeneration process can be represented by the following equations (1)-(3):

[0022] (1)

[0023] (2)

[0024] (3)

[0025] The physicochemical regeneration of deactivated mercury-removing adsorbents in solution is a multi-step heterogeneous physicochemical process involving diffusion, mass transfer, and chemical reactions. Mass transfer and diffusion are the key control steps in the adsorbent regeneration process. However, the most commonly used regeneration reactors in this field are heterogeneous reaction devices such as bubble beds, packed beds, and spray beds, which have shortcomings such as low diffusion and mass transfer rates and poor media mixing efficiency, which are not conducive to the industrial scale-up application of this technology. The impact regeneration device provided by this invention can utilize the impact flow to generate strong macroscopic and microscopic jets to efficiently enhance the heterogeneous process of multiphase mass transfer-diffusion-reaction. It has a very high efficiency in enhancing multiphase mixing, mass transfer, and diffusion (its enhancement efficiency is usually an order of magnitude higher than that of traditional reactors such as bubble beds), and has good application value.

[0026] In the field of regenerating deactivated mercury-removing adsorbents, most regeneration technologies generate wastewater and waste liquids (such as acids, alkalis, potassium permanganate, and chlorine-containing oxidants), which can lead to new secondary pollution problems, hindering the widespread application of related technologies. The free radical advanced oxidation technology provided by this invention primarily utilizes green free radicals to regenerate deactivated mercury-removing adsorbents. Compared to traditional adsorbent regeneration reagents, free radicals are recognized as green and clean oxidants; therefore, their regeneration process exhibits typical green and sustainable characteristics, making it a promising adsorbent regeneration reagent.

[0027] Existing mercury removal adsorbent regeneration processes require significant energy input, making most of the regeneration process energy-intensive, which hinders the large-scale application of related technologies. The regeneration method and system provided by this invention primarily utilize waste heat from boiler flue gas to provide the majority of the thermal energy required for solution heating, adsorbent drying, and regeneration processes. Overall, it has very low energy consumption, meets current low-carbon development strategies, and has significant engineering practical value.

[0028] In summary, compared with existing similar regeneration technologies, the method and system for regenerating deactivated mercury-removing adsorbents using ultraviolet light-fluid gas waste heat coupling and impact flow provided by this invention utilizes ultraviolet light synergistically with flue gas waste heat to induce highly active free radicals and impact flow coupling to regenerate deactivated mercury-removing adsorbents. This technology has comprehensive technical advantages such as simple device, high regeneration efficiency, high mixing / mass transfer / diffusion efficiency, energy saving and low carbon emissions, and green and environmentally friendly operation. It is a novel method and system for regenerating deactivated mercury-removing adsorbents with broad application prospects. Attached Figure Description

[0029] Figure 1 This is a front view of the deactivated mercury adsorbent regeneration device proposed in this invention.

[0030] Figure 2 The left view of the deactivated mercury adsorbent regeneration device proposed in this invention.

[0031] Reference numerals in the attached diagram: 1. Opposite-to-opposite-impact regeneration device; 2. High-speed nozzle; 3. Ultraviolet lamp; 4. Cover plate of opposite-to-opposite-impact regeneration device; 5. Material mixing and preheating tower; 6. Agitator; 7. Flue gas waste heat exchanger; 8. Liquid-solid separator; 9. Flue gas-air thermal drying and activation system; 10. Thermosiphon pipe; 11-12. Circulating pump; a. Regeneration reagent inlet; b. Deactivated mercury-removing adsorbent inlet; c. Mixed material outlet; e. Regenerated material outlet; f. Separated residual liquid discharge outlet; g. Separated adsorbent outlet; h. Dryed and activated adsorbent outlet. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited to the following.

[0033] The principle of the photo-thermal coupled strong jet regeneration method for deactivated mercury-removing adsorbents described in this invention is to utilize ultraviolet light and flue gas waste heat coupled with a countercurrent in a countercurrent regeneration device to induce the regeneration of highly active free radicals. The highly active free radicals can undergo vigorous chemical reactions with harmful substances covering the surface sites of the deactivated adsorbent, while the high-speed jet generated by the countercurrent impacts the covering material on the adsorbent surface and in the pores. The two processes synergistically regenerate the deactivated mercury-removing adsorbent from both chemical and physical perspectives. The method and apparatus for regenerating deactivated mercury-removing adsorbents provided by this invention have comprehensive advantages such as simple technology, high regeneration efficiency, high mass transfer and diffusion efficiency, energy saving and low carbon emissions, and green and environmentally friendly operation, making them valuable for industrial applications.

[0034] like Figure 1 and Figure 2 As shown, the system for regenerating deactivated mercury adsorbents using photo-thermal coupling high-pressure jets provided by this invention mainly includes an opposite-phase impact regeneration device 1 for regenerating deactivated mercury adsorbents, a high-speed nozzle 2 for spraying liquid-solid mixed media, an ultraviolet lamp 3 for radiation decomposition to regenerate reagent-induced free radicals, an opposite-phase impact regeneration device cover plate 4 for maintaining the opposite-phase impact regeneration device, a material mixing preheating tower 5 for mixing and preheating liquid and solid materials, a stirrer 6 for stirring liquid and solid materials to achieve uniform mixing, a flue gas waste heat exchanger 7 for heating the material temperature using flue gas waste heat, a liquid-solid separator 8 for rapidly separating the residual liquid and adsorbent after regeneration, a flue gas-air thermal drying and activation system 9 for drying and activating the adsorbent using flue gas waste heat, a thermosiphon pipe 10 for utilizing flue gas waste heat, and various supporting pipelines and circulation pumps 11-12, etc.

[0035] The impact regeneration device 1 is a rectangular reactor with multiple high-speed nozzles 2 and multiple ultraviolet lamps 3 on its sides, a top cover 4 with opposite impact regeneration devices, and a regenerated material outlet e at the lower right corner. Below the impact regeneration device 1 is a material mixing preheating tower 5. The material mixing preheating tower 5 has a regeneration reagent inlet a on its upper left, a deactivated mercury-removing adsorbent inlet b on its upper right, and mixed material outlets c and d on its left and right sides respectively. The material mixing preheating tower 5 contains a stirrer 6 and a flue gas waste heat exchanger 7. The material mixing preheating tower 5 and the impact regeneration device 1 are connected by pipelines to form a media transport and injection system, with two circulating pumps 11 and 12 on the pipelines. A liquid-solid separator 8 is connected to the regenerated material outlet e, and below it is a residual liquid discharge port f. The adsorbent outlet g on the left side is connected to a flue gas-air thermal drying and activation system 9. Below the flue gas-air thermal drying and activation system 9 is a dried and activated adsorbent outlet h, and inside it is a thermosiphon pipe 10.

[0036] The regeneration process of this system is as follows: Sodium persulfate and hydrogen peroxide, prepared at a certain concentration, are introduced into the material mixing and preheating tower 5 through the regeneration reagent inlet a. Meanwhile, the deactivated mercury-removing adsorbent is introduced into the material mixing and preheating tower 5 through the deactivated mercury-removing adsorbent inlet b. Simultaneously, the stirrer 6 and the flue gas waste heat exchanger 7 are started to mix and heat the medium. The uniformly mixed medium, heated to a certain temperature, is injected at high speed into the reaction zone of the impact regeneration device 1 through the first circulation pump 11 and the second circulation pump 12 via high-speed nozzles 2. Simultaneously, the ultraviolet lamp 3 is activated to emit ultraviolet light, which, together with the flue gas waste heat, decomposes the peroxides. The regeneration reagent induces various highly active free radicals, including hydroxyl radicals, sulfate radicals, and superoxide radicals. These highly active free radicals attack the harmful substances covering the active sites on the surface of the deactivated adsorbent. Simultaneously, the impact flow induces a powerful micro-jet to impact the residual substances on the deactivated adsorbent after free radical attack, removing the covering substances from the adsorbent surface from both chemical and physical perspectives, thereby achieving adsorbent regeneration. The regenerated residue and impurity mixture enters the liquid-solid separator 8 through the regenerated material outlet e for rapid liquid-solid separation. The separated residue is recycled and reused through the residual liquid discharge outlet f. For example, mercury resources can be recovered through precipitation, while sodium sulfate can be prepared as an industrial raw material through evaporation and crystallization using waste heat from flue gas. The separated solid adsorbent enters the flue gas-air thermal drying and activation system 9 through the adsorbent outlet g for further drying and activation. The heat energy required for drying and activation is provided by the thermosiphon pipe 10 using waste heat from the flue gas. The dried and activated adsorbent is recycled and reused through the dried and activated adsorbent outlet h, thus realizing the regeneration and reuse of the deactivated mercury-removing adsorbent. The energy of the entire deactivated adsorbent regeneration process is mainly derived from boiler flue gas waste heat, and the residue, slag, and by-products in the regeneration process are all recycled and reused. Therefore, the entire regeneration process has multiple characteristics such as energy saving, low carbon emissions, and green environmental protection, which is in line with the current strategy of promoting sustainable development.

[0037] In the aforementioned impact regeneration device 1, the high-speed nozzles 2 are arranged in a row with equal spacing in both the longitudinal and transverse directions, and the effective length range between the spacings A is 30 cm to 120 cm. The ultraviolet lamps 3 are arranged at the center of the diagonal of four adjacent high-speed nozzles 2 and are horizontally positioned, such as... Figure 1 and Figure 2 As shown, to obtain the maximum radiation range, the high-speed nozzles 2 arranged on both sides of the impact regeneration device 1 are coaxially opposed, and the effective range of the horizontal distance L between the two coaxially opposed nozzles is 40 cm ~ 200 cm.

[0038] In the aforementioned impact regeneration device 1, the effective ultraviolet radiation intensity range of the ultraviolet lamp 3 is 5 μW / cm². 2 ~300 μW / cm 2The effective range of the emission wavelength of the ultraviolet lamp 3 is between 180 nm and 280 nm.

[0039] The regeneration reagent is composed of a mixture of sodium persulfate and hydrogen peroxide. The concentration of sodium persulfate ranges from 0 mol / L to 3.2 mol / L, and the concentration of hydrogen peroxide ranges from 0 mol / L to 2.8 mol / L. The pH value of the regeneration reagent ranges from 0.01 to 8.5. The effective operating temperature of the regeneration device 1 is between 15℃ and 70℃, while the effective operating temperature of the flue gas-air thermal drying and activation system 9 is between 60℃ and 350℃.

[0040] The deactivated mercury removal adsorbent mainly includes one or more mixed adsorbents among carbon-based adsorbents such as porous carbon, biochar, and petroleum coke.

[0041] The following are implementation examples of the method and system's effect on adsorbent regeneration under different preliminary test conditions:

[0042] Example 1:

[0043] Taking self-made porous rice straw carbon as an example (initial mercury removal efficiency of 95.7%), the concentration of sodium persulfate was 0.1 mol / L, the concentration of hydrogen peroxide was 0.1 mol / L, the pH value of the mixed reagent was 1.8, the operating temperature was 50℃, the drying and activation temperature was 150℃, and the ultraviolet radiation intensity was 41 μW / cm². 2 The wavelength of the ultraviolet light was 254 nm. Preliminary results showed that the mercury removal efficiency after adsorbent regeneration was 41.2%.

[0044] Example 2:

[0045] Taking self-made porous rice straw carbon as an example (initial mercury removal efficiency of 95.7%), the concentration of sodium persulfate was 0.2 mol / L, the concentration of hydrogen peroxide was 0.1 mol / L, the pH value of the mixed reagent was 1.8, the operating temperature was 50℃, the drying and activation temperature was 150℃, and the ultraviolet radiation intensity was 41 μW / cm². 2 The wavelength of the ultraviolet light was 254 nm. Preliminary results showed that the mercury removal efficiency after adsorbent regeneration was 54.1%.

[0046] Example 3:

[0047] Taking self-made porous rice straw carbon as an example (initial mercury removal efficiency of 95.7%), the concentration of sodium persulfate was 0.2 mol / L, the concentration of hydrogen peroxide was 0.2 mol / L, the pH value of the mixed reagent was 1.8, the operating temperature was 50℃, the drying and activation temperature was 150℃, and the ultraviolet radiation intensity was 41 μW / cm². 2The wavelength of the ultraviolet light was 254 nm. Preliminary results showed that the mercury removal efficiency after adsorbent regeneration was 62.7%.

[0048] Example 4:

[0049] Taking self-made porous rice straw carbon as an example (initial mercury removal efficiency of 95.7%), the concentration of sodium persulfate was 0.2 mol / L, the concentration of hydrogen peroxide was 0.2 mol / L, the pH value of the mixed reagent was 1.8, the operating temperature was 60℃, the drying and activation temperature was 150℃, and the ultraviolet radiation intensity was 78 μW / cm². 2 The wavelength of the ultraviolet light was 254 nm. Preliminary results showed that the mercury removal efficiency after adsorbent regeneration was 74.5%.

[0050] Example 5:

[0051] Taking self-made porous rice straw carbon as an example (initial mercury removal efficiency of 95.7%), the concentration of sodium persulfate was 0.3 mol / L, the concentration of hydrogen peroxide was 0.2 mol / L, the pH value of the mixed reagent was 1.8, the operating temperature was 60℃, the drying and activation temperature was 150℃, and the ultraviolet radiation intensity was 78 μW / cm². 2 The wavelength of the ultraviolet light was 254 nm. Preliminary results showed that the mercury removal efficiency after adsorbent regeneration was 81.1%.

[0052] Example 6:

[0053] Taking self-made porous rice straw carbon as an example (initial mercury removal efficiency of 95.7%), the concentration of sodium persulfate was 0.3 mol / L, the concentration of hydrogen peroxide was 0.3 mol / L, the pH value of the mixed reagent was 1.8, the operating temperature was 60℃, the drying and activation temperature was 150℃, and the ultraviolet radiation intensity was 78 μW / cm². 2 The wavelength of the ultraviolet light was 254 nm. Preliminary results showed that the mercury removal efficiency after adsorbent regeneration was 88.1%.

[0054] Example 7:

[0055] Taking self-made porous rice straw carbon as an example (initial mercury removal efficiency of 95.7%), the concentration of sodium persulfate was 0.4 mol / L, the concentration of hydrogen peroxide was 0.3 mol / L, the pH value of the mixed reagent was 1.8, the operating temperature was 60℃, the drying and activation temperature was 150℃, and the ultraviolet radiation intensity was 78 μW / cm². 2 The wavelength of the ultraviolet light was 254 nm. Preliminary results showed that the mercury removal efficiency after adsorbent regeneration was 92.2%.

[0056] Example 8:

[0057] Taking self-made porous rice straw carbon as an example (initial mercury removal efficiency of 95.7%), the concentration of sodium persulfate was 0.4 mol / L, the concentration of hydrogen peroxide was 0.4 mol / L, the pH value of the mixed reagent was 1.8, the operating temperature was 60℃, the drying and activation temperature was 150℃, and the ultraviolet radiation intensity was 78 μW / cm². 2 The wavelength of the ultraviolet light was 254 nm. Preliminary results showed that the mercury removal efficiency after adsorbent regeneration was 94.1%.

[0058] As can be seen from the above embodiments, the regeneration method and system described in this invention can achieve high adsorbent regeneration efficiency and has comprehensive technical advantages such as simple equipment, energy saving and low carbon emissions, and environmentally friendly process, giving it significant technical and economic competitiveness. Furthermore, the embodiments described are preferred embodiments of this invention, but this invention is not limited to the above embodiments. Any obvious improvements, substitutions, or modifications that can be made by those skilled in the art without departing from the essence of this invention are within the protection scope of this invention.

Claims

1. A system for regenerating deactivated mercury adsorbents using a photo-thermal coupled strong jet, characterized in that, The main components include an opposite-phase impact regeneration device (1) for regenerating deactivated mercury adsorbent, multiple high-speed nozzles (2) placed on the inner wall of the opposite-phase impact regeneration device (1) for spraying liquid-solid mixing medium, an ultraviolet lamp (3) placed inside the opposite-phase impact regeneration device (1) for radiation decomposition and induction of free radicals by the regeneration reagent, a material mixing preheating tower (5) connected to the lower part of the opposite-phase impact regeneration device (1) for mixing and preheating liquid and solid materials, a stirrer (6) placed inside the material mixing preheating tower (5) for stirring liquid and solid materials to mix evenly, a flue gas waste heat exchanger (7) for heating the material temperature using flue gas waste heat, a liquid-solid separator (8) connected to the bottom of the opposite-phase impact regeneration device (1) for rapidly separating the residual liquid and adsorbent after regeneration, and a flue gas-air thermal drying and activation system (9) connected to the liquid-solid separator (8) for drying and activating the adsorbent using flue gas waste heat. The material mixing preheating tower (5) is provided with a regeneration reagent inlet a and a deactivated mercury adsorbent inlet b on the upper two sides respectively, and a mixed material outlet c and d on the left and right sides respectively, which are connected to the high-speed nozzle (2) to form a medium transport and spraying system; The flue gas-air thermal drying and activation system (9) is equipped with a thermosiphon (10) for utilizing the waste heat of flue gas.

2. The system for regenerating deactivated mercury adsorbents using a photo-thermal coupled strong jet according to claim 1, characterized in that, The aforementioned impact regeneration device (1) is a rectangular reactor with a cover plate (4) on top and a regenerated material outlet e at the bottom connected to a liquid-solid separator (8).

3. The system for regenerating deactivated mercury adsorbents using a photo-thermal coupled strong jet according to claim 1, characterized in that, The material mixing preheating tower (5) has a first circulating pump (11) and a second circulating pump (12) respectively installed on the pipeline between the material outlets c and d of the material mixing preheating tower (5) and the high-speed nozzle (2).

4. The system for regenerating deactivated mercury adsorbents using a photo-thermal coupled strong jet according to claim 1, characterized in that, The liquid-solid separator (8) has a residual liquid discharge port f below it and an adsorbent outlet g on its side connected to the flue gas-air thermal drying and activation system (9); the flue gas-air thermal drying and activation system (9) has an adsorbent outlet h below it.

5. The system for regenerating deactivated mercury adsorbents using a photo-thermal coupled strong jet according to claim 1, characterized in that, In the aforementioned impact regeneration device (1), the high-speed nozzles (2) are arranged at equal intervals in both the longitudinal and transverse directions, and the effective length range between the intervals A is 30 cm ~ 120 cm; the high-speed nozzles (2) arranged on both sides of the impact regeneration device (1) are arranged coaxially opposite each other, and the effective range of the horizontal distance L between the two coaxial opposite nozzles is 40 cm ~ 200 cm.

6. The system for regenerating deactivated mercury adsorbents using a photo-thermal coupled strong jet according to claim 1, characterized in that, The ultraviolet lamps (3) are arranged at the center of the diagonal of the four adjacent high-speed nozzles (2) and are set horizontally to obtain the maximum radiation range.

7. The system for regenerating deactivated mercury adsorbents using a photo-thermal coupled strong jet according to claim 1, characterized in that, In the aforementioned impact regeneration device (1), the effective ultraviolet radiation intensity range of the ultraviolet lamp (3) is within 5 μW / cm². 2 ~ 300μW / cm 2 The effective range of the emission wavelength of the ultraviolet lamp (3) is between 180 nm and 280 nm.

8. The system for regenerating deactivated mercury adsorbents using a photo-thermal coupled strong jet according to claim 1, characterized in that, The regeneration reagent is composed of sodium persulfate and hydrogen peroxide. The concentration of sodium persulfate is between 0 mol / L and 3.2 mol / L, and the concentration of hydrogen peroxide is between 0 mol / L and 2.8 mol / L. The pH value of the regeneration reagent is between 0.01 and 8.

5. The effective operating temperature of the regeneration device (1) is between 15℃ and 70℃, while the effective operating temperature of the flue gas-air thermal drying and activation system (9) is between 60℃ and 350℃.

9. The system for regenerating deactivated mercury adsorbents using a photo-thermal coupled strong jet according to claim 1, characterized in that, The deactivated mercury removal adsorbent includes one or more carbon-based adsorbents such as porous carbon, biochar, and petroleum coke.

10. A method for regenerating and deactivating mercury-removing adsorbents using a photo-thermal coupled strong jet based on the regeneration and deactivation mercury-removing adsorbent system according to any one of claims 1-9, characterized in that, Includes the following steps: S1. After the peroxide regeneration reagent sodium persulfate and hydrogen peroxide are mixed evenly, they are fed into the material mixing preheating tower (5) through the regeneration reagent inlet a. The deactivated mercury removal adsorbent is fed into the material mixing preheating tower (5) through the deactivated mercury removal adsorbent inlet b. The stirrer (6) and the flue gas waste heat exchanger (7) are started simultaneously to mix and heat the mixing medium of the two materials. S2. The uniformly mixed and preheated medium is injected into the reaction zone of the impact regeneration device (1) at high speed through the first circulation pump (11) and the second circulation pump (12) respectively by the high-speed nozzle (2). At the same time, the ultraviolet lamp (3) is activated to emit ultraviolet light and decompose the peroxide regeneration reagent in synergistic way with the waste heat of flue gas, inducing the generation of hydroxyl radicals, sulfate radicals and superoxide radicals. The free radicals attack the covering material on the active site of the deactivated adsorbent surface. At the same time, the ultra-strong micro-jet induced by the impact flow impacts the residual material on the adsorbent after being attacked by free radicals, and removes the covering material on the adsorbent surface from both chemical and physical aspects, so as to realize the regeneration of the adsorbent. S3. The mixture of residual liquid and impurities after regeneration enters the liquid-solid separator (8) from the regenerated material outlet e for liquid-solid separation; the residual liquid after separation is recycled and reused through the residual liquid discharge outlet f; the solid adsorbent after separation enters the flue gas-air thermal drying and activation system (9) from the adsorbent outlet g for drying and activation; the heat energy required for drying and activation is heated by the thermosiphon (10) using the waste heat of the flue gas; the adsorbent after drying and activation is recycled and reused through the adsorbent outlet h.

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