Hybrid desulfurization and denitrification equipment and treatment process for ship exhaust gas treatment

Abstract

The present invention relates to a hybrid desulfurization and denitrification equipment and treatment process for ship exhaust gas treatment, and belongs to the technical field of ship exhaust gas desulfurization and denitrification treatment. The desulfurization and denitrification equipment provided by the present invention is simple, and only includes a heat exchange mechanism, a photocatalytic reaction mechanism and a seawater storage mechanism. The overall operation steps of the equipment are easy to understand, and the error rate of operators is low. The core point of the treatment process provided by the present invention is to pump the ship exhaust gas into a photocatalytic reactor for reaction. The photocatalytic reactor is equipped with a filler, and the filler raw material is activated carbon fiber. The present invention uses concentrated sulfuric acid to pretreat the activated carbon fiber to increase its adsorption capacity; maleic anhydride is added to pave a good foundation for the subsequent uniform loading of metal oxide ions; hexadecyltrimethylammonium bromide is added to reduce the agglomeration of loaded particles in the system; the present invention also simultaneously modifies the activated carbon fiber with titanium dioxide and cuprous oxide, thereby increasing the active sites on the surface of the activated carbon fiber, thereby achieving excellent desulfurization and denitrification effects.

Description

Technical Field

[0001] The present invention belongs to the technical field of ship exhaust gas desulfurization and denitrification treatment, and in particular relates to a hybrid desulfurization and denitrification equipment and treatment process for ship exhaust gas treatment. Background Art

[0002] Air pollution is receiving increasing attention due to its severe damage to the health of Earth's ecosystems and threats to human health and safety. Simultaneously, with the rapid development of the global shipping industry, atmospheric pollution from ship exhaust is becoming increasingly severe. Marine diesel engines, burning relatively low-quality heavy fuel oil, release exhaust gases with a complex composition of pollutants, primarily sulfur oxides and nitrogen oxides, as well as CO, HC, and PM. Due to the high excess air coefficient and more complete combustion during diesel engine combustion, sulfur oxides and nitrogen oxides dominate the exhaust gas, making them the most harmful pollutants. These are listed by the International Maritime Organization as primary controlled ship exhaust pollutants, and can cause environmental acidification, damage tropospheric ozone, and accumulate nutrients, posing a threat to global human health.

[0003] To prevent air pollution from ships and strengthen the protection of the marine ecosystem, the International Maritime Organization (IMO) has established a series of pollution prevention conventions to limit ship exhaust emissions. To meet the IMO's emission limits, ship exhaust must be purified, typically through desulfurization and denitrification. Existing ship exhaust treatment processes and equipment are limited in scope, some of which are complex and difficult to operate, and their desulfurization and denitrification effects are suboptimal. Therefore, the need for improved ship exhaust treatment is urgent, and the development of simple desulfurization and denitrification equipment and a process with superior desulfurization and denitrification effects is of great practical significance. Summary of the Invention

[0004] The present invention aims to provide a hybrid desulfurization and denitrification equipment and treatment process for treating ship exhaust gas. The desulfurization and denitrification equipment provided by the present invention is simple and only includes a heat exchange mechanism, a photocatalytic reaction mechanism, and a seawater storage mechanism. The overall operation steps of the equipment are easy to understand, which reduces the error rate of operators. The core point of the treatment process provided by the present invention is to pump the ship exhaust gas into a photocatalytic reactor for reaction. The photocatalytic reactor is equipped with a filler, and the filler raw material is activated carbon fiber. The present invention uses concentrated sulfuric acid to pretreat the activated carbon fiber to increase its adsorption capacity; adds maleic anhydride to pave a good foundation for the subsequent uniform loading of metal oxide ions; adds hexadecyltrimethylammonium bromide to reduce the agglomeration of loaded particles in the system; and the present invention also simultaneously modifies the activated carbon fiber with titanium dioxide and cuprous oxide to increase the active sites on the surface of the activated carbon fiber, thereby achieving excellent desulfurization and denitrification effects, solving the problems of complex ship exhaust gas desulfurization and denitrification equipment and poor desulfurization and denitrification effects of its treatment process in the prior art.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A hybrid desulfurization and denitrification process for treating ship exhaust gas comprises the following steps:

[0007] S10, inputting the ship exhaust gas into a heat exchanger for heat exchange, then controlling the flow rate of the ship exhaust gas, pumping the ship exhaust gas from the bottom of the photocatalytic reactor into the photocatalytic reactor, simultaneously starting a water pump and adjusting a first flow meter to control the liquid-to-gas ratio of seawater and ship exhaust gas, and pumping seawater from a seawater storage tank into the photocatalytic reactor from the top of the photocatalytic reactor for seawater spraying; spraying the seawater further cools the ship exhaust gas and effectively captures particulate matter in the exhaust gas;

[0008] S20. Turn on the flue gas analyzers at the inlet and outlet of the photocatalytic reactor to monitor changes in the concentrations of nitrogen monoxide and sulfur dioxide, turn on the vacuum ultraviolet lamp for illumination, adjust the temperature of the photocatalytic reactor, and adjust the humidity of the exhaust gas in the photocatalytic reactor. The exhaust gas passes through the packing bed limiting device with fillers in the photocatalytic reactor and reacts for 1-1.5 hours. After the reaction is completed, the product is recovered or recycled, and the treated gas is discharged from the chimney.

[0009] Furthermore, in step S10, the ship exhaust gas flow rate is 0.12-0.15m 3 / h, the liquid-gas ratio of seawater and ship exhaust gas is 0.6-0.7L / m 3 .

[0010] Furthermore, in step S20, the irradiation power of the vacuum ultraviolet lamp is 10-15W, and the vacuum ultraviolet lamp simultaneously outputs ultraviolet light with a central wavelength of 254-275nm and vacuum ultraviolet light of 185-200nm, and the vacuum ultraviolet light of 185-200nm accounts for approximately 6% of the total irradiation power; the temperature of the photocatalytic reactor is 60-70°C; and the humidity is 0.006-0.007.

[0011] Furthermore, the method for preparing the filler in step S20 includes the following steps:

[0012] S21. Pretreating the activated carbon fiber to obtain a first carbon fiber and preparing a suspension:

[0013] S211, rinsing the activated carbon fiber with deionized water, then immersing it in concentrated sulfuric acid for liquid-phase oxidation, then washing it with deionized water until the activated carbon fiber is neutral, drying it under controlled temperature to obtain a first carbon fiber, and cutting the first carbon fiber for later use;

[0014] S212, adding nano titanium dioxide to the copper sulfate solution, adding sodium hydroxide solution dropwise while stirring to react, then adding hydrazine hydrate aqueous solution dropwise while controlling the temperature and stirring and continuing to stir to obtain a suspension, which is set aside;

[0015] S22. Weigh the first carbon fiber, then add maleic anhydride and hexadecyltrimethylammonium bromide in sequence to react for 1-1.5 hours, then add the suspension and control the temperature to react. After the reaction is completed, the second carbon fiber is obtained. The second carbon fiber is washed with deionized water and anhydrous ethanol in sequence, and then dried under controlled temperature to obtain a filler.

[0016] Furthermore, in step S211, the number of deionized water rinses is 3-5 times, the volume of concentrated sulfuric acid added is enough to completely cover the activated carbon fiber, the liquid-phase oxidation conditions are heating in a water bath at 60-80°C for 2-2.5h, the temperature of the temperature-controlled drying is 115-125°C, and the first carbon fiber is cut into squares with a thickness of 2-3mm.

[0017] Furthermore, in step S212, the dosage ratio of the nano-titanium dioxide, copper sulfate solution, sodium hydroxide solution and hydrazine hydrate aqueous solution is 78-85 g: 35-45 mL: 190-220 mL: 48-55 mL.

[0018] Furthermore, the concentrations of the copper sulfate solution, sodium hydroxide solution and hydrazine hydrate aqueous solution in step S212 are all 0.2 mol / L.

[0019] Furthermore, in step S212, the reaction time is 20-30 min, the temperature control temperature is 65-70° C., and the continuous stirring time is 1-1.5 h.

[0020] Furthermore, in step S22, the weight ratio of the first carbon fiber, maleic anhydride, hexadecyltrimethylammonium bromide and suspension is 8-12:5-7:2-3:230-280, the temperature of the temperature-controlled reaction is 52-58°C and the time is 3-4h, the number of washing times with deionized water and anhydrous ethanol is 3-4 times, and the temperature of the temperature-controlled drying is 60-70°C and the time is 10-12h.

[0021] As a further embodiment of the present invention, a hybrid desulfurization and denitrification device for treating ship exhaust gas is provided, wherein the hybrid desulfurization and denitrification device comprises a heat exchange mechanism, a photocatalytic reaction mechanism, and a seawater storage mechanism; the heat exchange mechanism is located on one side of the photocatalytic reaction mechanism, and the seawater storage mechanism is located on the other side of the photocatalytic reaction mechanism;

[0022] The photocatalytic reaction mechanism includes a photocatalytic reactor, a water vapor generator, a flue gas analyzer and a heating jacket, the output end of the water vapor generator is connected to the bottom end of the photocatalytic reactor, the heating jacket is wrapped around the bottom of the photocatalytic reactor shell, and the flue gas analyzer is connected to the inlet and outlet pipes of the photocatalytic reactor; a vacuum ultraviolet lamp, a packing bed limiting device and a sprayer are provided in the photocatalytic reactor, the vacuum ultraviolet lamp is located in the center of the photocatalytic reactor, and its top is fixedly connected to the inner wall of the top of the photocatalytic reactor, the top of the vacuum ultraviolet lamp is also connected to a ballast, the ballast is located outside the top of the photocatalytic reactor, the packing bed limiting device is located between the vacuum ultraviolet lamp and the inner wall of the photocatalytic reactor and is connected to the inner wall of the photocatalytic reactor, the sprayer is located above the packing bed limiting device and passes through the pipe of the sprayer through the photocatalytic reactor shell and is fixedly connected to the photocatalytic reactor.

[0023] The entire photocatalytic reactor is made of stainless steel, which effectively prevents the inner wall of the photocatalytic reactor from being corroded. In addition, the ballast of the vacuum ultraviolet lamp is placed outside the photocatalytic reactor to effectively prevent the photocatalytic reactor from leaking electricity and being corroded by sulfur dioxide and nitrogen oxides.

[0024] Furthermore, the heat exchange mechanism includes a heat exchanger, one end of the heat exchanger is connected to the ship exhaust gas input pipe, the other end of the heat exchanger is provided with a pneumatic booster pump and connected to the input end of the pneumatic booster pump, and the output end of the pneumatic booster pump is connected to the air inlet of the photocatalytic reactor.

[0025] Furthermore, the seawater storage mechanism includes a seawater storage tank, the outlet pipe of the seawater storage tank is provided with a water pump and connected to the input end of the water pump, the output end of the water pump is provided with a first flow meter, the input end of the first flow meter is connected to the output end of the water pump, and the output end of the first flow meter is connected to the spray port of the photocatalytic reactor.

[0026] Beneficial effects of the present invention:

[0027] (1) The present invention first pre-treats the activated carbon fiber with concentrated sulfuric acid, and increases the polar oxygen-containing functional groups on the surface of the activated carbon fiber by liquid phase oxidation, thereby helping to increase its adsorption capacity; maleic anhydride is added to graft the activated carbon fiber, repairing some surface defects caused by concentrated sulfuric acid phase oxidation, creating favorable conditions for increasing the active sites on the surface of the activated carbon fiber, and laying a good foundation for the subsequent uniform loading of metal oxide ions; hexadecyltrimethylammonium bromide is added as a surfactant to reduce the agglomeration of loaded particles in the system, making the system relatively stable, which is conducive to the desulfurization and denitrification.

[0028] (2) The present invention adds nano-titanium dioxide and copper sulfate solution, and simultaneously modifies the activated carbon fiber with titanium dioxide and cuprous oxide, thereby increasing the active sites on the surface of the activated carbon fiber and combining with the oxygen-containing functional groups on the surface of the activated carbon fiber, further promoting the catalytic oxidation and re-adsorption of harmful gases such as sulfur dioxide and nitrogen monoxide at each active site, thereby achieving excellent desulfurization and denitrification effects.

[0029] (3) The hybrid desulfurization and denitrification equipment provided by the present invention is simple and only includes three major mechanisms: a heat exchange mechanism, a photocatalytic reaction mechanism, and a seawater storage mechanism. The overall operation steps of the equipment are easy to understand, making it easy for operators to operate with a low error rate. At the same time, the entire photocatalytic reactor is made of stainless steel, which effectively prevents the inner wall of the photocatalytic reactor from being corroded. In addition, the ballast of the vacuum ultraviolet lamp is placed outside the photocatalytic reactor, which effectively prevents the photocatalytic reactor from leaking electricity and being corroded by sulfur dioxide and nitrogen oxides. DETAILED DESCRIPTION

[0030] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention. Example 1

[0031] Preparation of filler, the preparation method comprises the following steps:

[0032] S21. Pretreating the activated carbon fiber to obtain a first carbon fiber and preparing a suspension:

[0033] S211, the purchased activated carbon fiber was rinsed with deionized water three times, and then completely immersed in concentrated sulfuric acid and heated in a water bath at 60°C for 2.5 hours for liquid phase oxidation. After the oxidation, it was washed with deionized water until the activated carbon fiber was neutral, and dried at 120°C to obtain a first carbon fiber. The first carbon fiber was cut into squares with a thickness of 2 mm for later use;

[0034] S212, 81g of nano-titanium dioxide was added to 45mL of a 0.2mol / L copper sulfate solution, and 205mL of a 0.2mol / L sodium hydroxide solution was added dropwise while stirring, and the mixture was reacted for 30min. Then, 55mL of a 0.2mol / L hydrazine hydrate aqueous solution was added dropwise while controlling the temperature at 65°C and stirring, and the mixture was stirred for 1h to obtain a suspension, which was set aside;

[0035] S22. Weigh 12 parts by weight of the first carbon fiber, then add 6 parts by weight of maleic anhydride and 3 parts by weight of hexadecyltrimethylammonium bromide in turn to react for 1 hour, then add 230 parts by weight of the suspension, control the temperature at 52°C to react for 3 hours, and after the reaction is completed, obtain the second carbon fiber. Wash the second carbon fiber with deionized water and anhydrous ethanol 4 times in turn, then control the temperature at 65°C to dry for 10 hours to obtain the filler. Example 2

[0036] Preparation of filler, the preparation method comprises the following steps:

[0037] S21. Pretreating the activated carbon fiber to obtain a first carbon fiber and preparing a suspension:

[0038] S211, the purchased activated carbon fiber was rinsed with deionized water four times, and then completely immersed in concentrated sulfuric acid and heated in a water bath at 80°C for 2 hours for liquid phase oxidation. After the oxidation, it was washed with deionized water until the activated carbon fiber was neutral, and dried at 126°C to obtain a first carbon fiber. The first carbon fiber was cut into squares with a thickness of 3 mm for later use;

[0039] S212, 78g of nano-titanium dioxide was added to 35mL of a 0.2mol / L copper sulfate solution, and 220mL of a 0.2mol / L sodium hydroxide solution was added dropwise while stirring, and the reaction was carried out for 25min. Then, 51mL of a 0.2mol / L hydrazine hydrate aqueous solution was added dropwise while controlling the temperature at 70°C and stirring, and the stirring was continued for 1.5h to obtain a suspension, which was set aside;

[0040] S22. Weigh 10 parts by weight of the first carbon fiber, then add 7 parts by weight of maleic anhydride and 2 parts by weight of hexadecyltrimethylammonium bromide in turn, react for 1.5 hours, then add 255 parts by weight of the suspension, control the temperature at 55°C and react for 4 hours. After the reaction is completed, obtain the second carbon fiber. Wash the second carbon fiber with deionized water and anhydrous ethanol 4 times in turn, then control the temperature at 60°C and dry for 11 hours to obtain the filler. Example 3

[0041] Preparation of filler, the preparation method comprises the following steps:

[0042] S21. Pretreating the activated carbon fiber to obtain a first carbon fiber and preparing a suspension:

[0043] S211, the purchased activated carbon fiber was rinsed with deionized water 5 times, and then completely immersed in concentrated sulfuric acid and heated in a water bath at 70°C for 2 hours for liquid phase oxidation. After the oxidation, it was washed with deionized water until the activated carbon fiber was neutral, and then dried at 113°C to obtain a first carbon fiber. The first carbon fiber was cut into squares with a thickness of 2.5 mm for later use;

[0044] S212, 85g of nano-titanium dioxide was added to 40mL of 0.2mol / L copper sulfate solution, and 190mL of 0.2mol / L sodium hydroxide solution was added dropwise while stirring, and the reaction was carried out for 20min. Then, 48mL of 0.2mol / L hydrazine hydrate aqueous solution was added dropwise while controlling the temperature at 70°C and stirring, and the stirring was continued for 1h to obtain a suspension, which was set aside;

[0045] S22. Weigh 8 parts by weight of the first carbon fiber, then add 5 parts by weight of maleic anhydride and 2 parts by weight of hexadecyltrimethylammonium bromide in sequence and react for 1 hour, then add 280 parts by weight of the suspension, control the temperature at 58°C and react for 3 hours. After the reaction is completed, obtain the second carbon fiber, wash the second carbon fiber with deionized water and anhydrous ethanol for 3 times in sequence, then control the temperature at 70°C and dry it for 12 hours to obtain the filler.

[0046] Comparative Example 1

[0047] Compared with Example 3, concentrated sulfuric acid is not used to pretreat the activated carbon fiber in Comparative Example 1, that is, step S211 is: the purchased activated carbon fiber is rinsed with deionized water 5 times, and dried at a controlled temperature of 113°C to obtain the first carbon fiber, and the first carbon fiber is cut into squares with a thickness of 2.5 mm for standby use; the other parameters are consistent with the preparation method.

[0048] Comparative Example 2

[0049] Compared with Example 3, in Comparative Example 2, no maleic anhydride was added, and the amount of cetyltrimethylammonium bromide added was 7 parts by weight, and the other parameters were consistent with the preparation method.

[0050] Comparative Example 3

[0051] Compared with Example 3, in Comparative Example 3, hexadecyltrimethylammonium bromide was not added, and the amount of maleic anhydride added was 7 parts by weight, and the other parameters were consistent with the preparation method.

[0052] Comparative Example 4

[0053] Compared with Example 3, the addition amount of nano-titanium dioxide in Comparative Example 4 is 76 g, and the other parameters and preparation methods are the same.

[0054] Comparative Example 5

[0055] Compared with Example 3, the added amount of nano-titanium dioxide in Comparative Example 5 is 87 g, and the other parameters and preparation methods are the same.

[0056] Comparative Example 6

[0057] Compared with Example 3, the amount of copper sulfate solution added in Comparative Example 4 is 180 mL, and the other parameters are consistent with the preparation method.

[0058] Comparative Example 7

[0059] Compared with Example 3, the amount of copper sulfate solution added in Comparative Example 4 is 230 mL, and the other parameters and preparation methods are the same. Example 4

[0060] A hybrid desulfurization and denitrification process for treating ship exhaust gas comprises the following steps:

[0061] S10, the ship's exhaust gas is fed into the heat exchanger through the pipeline for heat exchange, and the exhaust gas flow rate of the ship is controlled to 0.15m 3 / h, the ship exhaust gas is pumped into the photocatalytic reactor from the bottom air inlet of the photocatalytic reactor through a pneumatic booster pump, and at the same time the water pump is started and the first flow meter is adjusted to control the liquid-gas ratio of seawater and ship exhaust gas to 0.6L / m 3 , pumping seawater in the seawater storage tank from the top of the photocatalytic reactor into the photocatalytic reactor for spraying seawater;

[0062] S20. Turn on the flue gas analyzers at the inlet and outlet of the photocatalytic reactor to monitor changes in the concentrations of nitric oxide and sulfur dioxide, turn on the vacuum ultraviolet lamp and adjust its irradiation power to 12W for illumination, adjust the heating jacket to control the temperature in the photocatalytic reactor to 65°C, and adjust the water vapor generator to control the humidity of the exhaust gas in the photocatalytic reactor to 0.007. The exhaust gas passes through the packing bed limiting device prepared in Example 3 in the photocatalytic reactor and reacts for 1 hour. After the reaction is completed, the product is recovered or recycled, and the treated gas is discharged from the chimney.

[0063] In step S20, the vacuum ultraviolet lamp simultaneously outputs ultraviolet light with a central wavelength of 254 nm and vacuum ultraviolet light with a wavelength of 200 nm, and the vacuum ultraviolet light with a wavelength of 200 nm accounts for about 6% of the total irradiation power. Example 5

[0064] Compared with Example 4, the ship exhaust gas flow rate in step S10 is 0.12m 3 / h; in step S20, the irradiation power is 10W, the temperature in the photocatalytic reactor is 70°C, and the exhaust gas humidity is 0.006, and the filler prepared in Example 3 is replaced with the filler prepared in Example 1 and reacted for 1.5h;

[0065] The vacuum ultraviolet lamp simultaneously outputs ultraviolet light with a central wavelength of 275nm and vacuum ultraviolet light of 200nm, and the 200nm vacuum ultraviolet light accounts for about 6% of the total irradiation power;

[0066] The remaining parameters and operation steps remain unchanged and will not be repeated here. Example 6

[0067] Compared with Example 4, the ship exhaust gas flow rate in step S10 is 0.14m3 / h, the liquid-gas ratio of seawater and ship exhaust gas is 0.7L / m 3 In step S20, the irradiation power is 15W, the temperature in the photocatalytic reactor is 60°C, and the filler prepared in Example 3 is replaced with the filler prepared in Example 2;

[0068] The vacuum ultraviolet lamp simultaneously outputs ultraviolet light with a central wavelength of 254nm and vacuum ultraviolet light of 185nm, and the vacuum ultraviolet light of 185nm accounts for about 6% of the total irradiation power;

[0069] The remaining parameters and operation steps remain unchanged and will not be repeated here.

[0070] Comparative Examples 8-14

[0071] Compared with Example 4, in Comparative Examples 8-14, the fillers used in step S20 are the fillers prepared in Comparative Examples 1-7, respectively, and the other parameters and treatment processes are the same.

[0072] Comparative Example 15

[0073] Compared with Example 4, the ship exhaust gas flow rate in step S10 in Comparative Example 15 is 0.10m 3 / h, and the other parameters are consistent with the treatment process.

[0074] Comparative Example 16

[0075] Compared with Example 4, the ship exhaust gas flow rate in step S10 in Comparative Example 16 is 0.17m 3 / h, and the other parameters are consistent with the treatment process.

[0076] Comparative Example 17

[0077] Compared with Example 4, the liquid-gas ratio of seawater and ship exhaust gas in step S10 in Comparative Example 17 is 0.5 L / m 3 , the other parameters are consistent with the treatment process.

[0078] Comparative Example 18

[0079] Compared with Example 4, the liquid-gas ratio of seawater and ship exhaust gas in step S10 in Comparative Example 18 is 0.8 L / m 3 , the other parameters are consistent with the treatment process. Example 7

[0080] A hybrid desulfurization and denitrification device for treating ship exhaust gas comprises a heat exchange mechanism, a photocatalytic reaction mechanism and a seawater storage mechanism; the heat exchange mechanism is located on one side of the photocatalytic reaction mechanism, and the seawater storage mechanism is located on the other side of the photocatalytic reaction mechanism.

[0081] The photocatalytic reaction mechanism includes a photocatalytic reactor, a water vapor generator, a flue gas analyzer and a heating jacket, wherein the output end of the water vapor generator is connected to the bottom end of the photocatalytic reactor, the heating jacket is wrapped around the bottom of the photocatalytic reactor shell, and the flue gas analyzer is connected to the inlet and outlet pipes of the photocatalytic reactor; a vacuum ultraviolet lamp is provided in the photocatalytic reactor, the vacuum ultraviolet lamp is located in the center of the photocatalytic reactor, and the top of the vacuum ultraviolet lamp is fixedly connected to the inner wall of the top of the photocatalytic reactor. A ballast is also connected to the top of the vacuum ultraviolet lamp, and the ballast is located outside the top of the photocatalytic reactor; a packing bed limiting device is provided between the vacuum ultraviolet lamp and the inner wall of the photocatalytic reactor, the packing bed limiting device is fixedly connected to the photocatalytic reactor, and a sprayer is installed above the packing bed limiting device, and the pipe of the sprayer passes through the photocatalytic reactor shell and is fixedly connected to the photocatalytic reactor;

[0082] The heat exchange mechanism includes a heat exchanger, one end of which is connected to a ship exhaust gas input pipe, and the other end of which is provided with a pneumatic booster pump and connected to the input end of the pneumatic booster pump, and the output end of the pneumatic booster pump is connected to the air inlet of the photocatalytic reactor.

[0083] The seawater storage mechanism includes a seawater storage tank, the outlet pipe of the seawater storage tank is provided with a water pump and is connected to the input end of the water pump, the output end of the water pump is provided with a first flow meter, the input end of the first flow meter is connected to the output end of the water pump, and the output end of the first flow meter is connected to the spray port of the photocatalytic reactor.

[0084] Performance testing

[0085] The removal rates of the desulfurization and denitrification treatment processes of Examples 4-6 and Comparative Examples 8-18 were calculated based on the inlet sulfur dioxide, nitrogen monoxide and outlet sulfur dioxide, nitrogen monoxide concentrations measured by the flue gas analyzer. The formula is:

[0086] ;

[0087] The results are shown in Table 1.

[0088] Table 1

[0089]

[0090] As shown in Table 1, the hybrid desulfurization and denitrification process for ship exhaust gas treatment provided by the present invention has outstanding desulfurization and denitrification effects.

[0091] Throughout the specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0092] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in similar ways. As long as they do not deviate from the invention or exceed the scope defined by the claims, they should all fall within the scope of protection of the present invention.

Claims

1. A hybrid desulfurization and denitrification process for ship exhaust gas treatment, characterized in that: The treatment process comprises the following steps: S10, inputting the ship exhaust gas into the heat exchanger for heat exchange, then controlling the flow rate of the ship exhaust gas to pump the ship exhaust gas from the bottom of the photocatalytic reactor into the photocatalytic reactor, simultaneously starting a water pump and adjusting a first flow meter to control the liquid-to-gas ratio of seawater and the ship exhaust gas, and pumping seawater from the seawater storage tank into the photocatalytic reactor from the top of the photocatalytic reactor for seawater spraying; S20. Turn on the flue gas analyzers at the inlet and outlet of the photocatalytic reactor to monitor changes in the concentrations of nitric oxide and sulfur dioxide, turn on the vacuum ultraviolet lamp for illumination, adjust the temperature of the photocatalytic reactor, and adjust the humidity of the exhaust gas in the photocatalytic reactor. The exhaust gas passes through a packed bed limiting device with fillers in the photocatalytic reactor and reacts for 1-1.5 hours. After the reaction is completed, the product is recovered or recycled, and the treated gas is discharged from the chimney; The method for preparing the filler in step S20 comprises the following steps: S21, pretreating the activated carbon fiber to obtain a first carbon fiber, and preparing a suspension; S22, weighing the first carbon fiber, then adding maleic anhydride and hexadecyltrimethylammonium bromide in sequence, reacting for 1-1.5 hours, then adding the suspension, controlling the temperature to react, and obtaining the second carbon fiber after the reaction is complete. The second carbon fiber is washed with deionized water and anhydrous ethanol in sequence, and then drying under controlled temperature to obtain a filler; The specific operations of step S21 are: S211, rinsing the activated carbon fiber with deionized water, then immersing it in concentrated sulfuric acid for liquid-phase oxidation, then washing it with deionized water until the activated carbon fiber is neutral, drying it under controlled temperature to obtain a first carbon fiber, and cutting the first carbon fiber for later use; S212. Add nano-titanium dioxide to copper sulfate solution, add sodium hydroxide solution dropwise while stirring to react, then add hydrazine hydrate aqueous solution dropwise while controlling the temperature and stirring and continue stirring to obtain a suspension for later use.

2. The hybrid desulfurization and denitrification process for ship exhaust gas treatment according to claim 1, characterized in that: The ship exhaust gas flow rate in step S10 is 0.12-0.15m 3 / h, the liquid-gas ratio of seawater and ship exhaust gas is 0.6-0.7L / m 3 .

3. The hybrid desulfurization and denitrification process for ship exhaust gas treatment according to claim 1, characterized in that: In step S20, the irradiation power of the vacuum ultraviolet lamp is 10-15W. The vacuum ultraviolet lamp simultaneously outputs ultraviolet light with a central wavelength of 254-275nm and vacuum ultraviolet light of 185-200nm, and the vacuum ultraviolet light of 185-200nm accounts for about 6% of the total irradiation power; the temperature of the photocatalytic reactor is 60-70°C; and the humidity is 0.006-0.

007.

4. The hybrid desulfurization and denitrification process for ship exhaust gas treatment according to claim 1, characterized in that: In step S212, the dosage ratio of nano-titanium dioxide, copper sulfate solution, sodium hydroxide solution and hydrazine hydrate aqueous solution is 78-85 g:35-45 mL:190-220 mL:48-55 mL; the concentrations of the copper sulfate solution, sodium hydroxide solution and hydrazine hydrate aqueous solution are all 0.2 mol / L.

5. The hybrid desulfurization and denitrification process for ship exhaust gas treatment according to claim 1, characterized in that: In step S22, the weight ratio of the first carbon fiber, maleic anhydride, hexadecyltrimethylammonium bromide and suspension is 8-12:5-7:2-3:230-280.

6. A hybrid desulfurization and denitrification treatment process for ship exhaust gas treatment according to any one of claims 1 to 5, characterized in that: The device includes a heat exchange mechanism, a photocatalytic reaction mechanism and a seawater storage mechanism; the heat exchange mechanism is located on one side of the photocatalytic reaction mechanism, and the seawater storage mechanism is located on the other side of the photocatalytic reaction mechanism; The photocatalytic reactor is provided with a vacuum ultraviolet lamp, a packing bed limiting device and a sprayer. The vacuum ultraviolet lamp is located in the center of the photocatalytic reactor, and its top is fixedly connected to the inner wall of the top of the photocatalytic reactor. The top of the vacuum ultraviolet lamp is also connected to a ballast, and the ballast is located outside the top of the photocatalytic reactor. The packing bed limiting device is located between the vacuum ultraviolet lamp and the inner wall of the photocatalytic reactor and is connected to the inner wall of the photocatalytic reactor. The sprayer is located above the packing bed limiting device and passes through the pipe of the sprayer to penetrate the photocatalytic reactor shell and is fixedly connected to the photocatalytic reactor.

7. The equipment for the hybrid desulfurization and denitrification process for treating ship exhaust gas according to claim 6, characterized in that: The heat exchange mechanism includes a heat exchanger, one end of which is connected to a ship exhaust gas input pipe, and the other end of which is provided with a pneumatic booster pump and connected to the input end of the pneumatic booster pump, and the output end of the pneumatic booster pump is connected to the air inlet of the photocatalytic reactor.

8. The equipment for the hybrid desulfurization and denitrification process for treating ship exhaust gas according to claim 6, characterized in that: The seawater storage mechanism includes a seawater storage tank, the outlet pipe of the seawater storage tank is provided with a water pump and is connected to the input end of the water pump, the output end of the water pump is provided with a first flow meter, the input end of the first flow meter is connected to the output end of the water pump, and the output end of the first flow meter is connected to the spray port of the photocatalytic reactor.

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