Sulfur-resistant regenerating agent for denitration catalyst and method for regenerating denitration catalyst

Abstract

The application discloses a kind of denitration catalyst sulfur-resistant regeneration reagent and denitration catalyst regeneration method, and denitration catalyst sulfur-resistant regeneration reagent includes: pre-washing reagent and active load reagent;Wherein, pre-washing reagent includes: citric acid 1-5%, triethanolamine 0.2-2%, sulfuric acid 0.05-5%, alkyl glycoside 0.1-2%, dodecyl trimethyl ammonium bromide 0.3-4%, the rest is water, by mass;Active load reagent includes: cerium nitrate 0.1-2%, ammonium molybdate 0.2-2%, vanadium salt 3-5%, tungsten salt 1-5%, sulfuric acid 0.1-2%, citric acid 0.1-1%, JFC penetrant 0.1-0.3%, the rest is water, by mass.The denitration catalyst sulfur-resistant regeneration reagent of the application can better restore the specific surface area of catalyst, better remove the ash in pore surface and micropore, and the poisoning phenomenon of sulfur substances and the enrichment phenomenon of alkali metals basically disappear.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of catalyst regeneration, in particular, the present application relates to a kind of denitration catalyst sulfur resistance regeneration reagent and denitration catalyst regeneration method. BACKGROUND

[0002] The denitration catalyst is used for treating NO x Atmospheric pollutants, with the increasing environmental protection requirements, the disposal demand of waste catalyst produced by SCR denitration increases sharply, and the disposal difficulty also increases continuously. The smoke temperature of steel, coking and other non-electricity industries is low (<300 DEG C), the composition is complex, the working condition fluctuates greatly, and the dry / half dry desulfurization (sodium base)-dust removal-low temperature SCR denitration process is the mainstream process of flue gas treatment in coking industry at present, and the stable and efficient operation of low temperature SCR denitration catalyst is crucial to flue gas denitration. The by-products such as Na2SO3, Na2SO4 and Na2CO3 produced in the process also need further treatment.

[0003] The particularity of non-electricity industry flue gas treatment process is easy to cause low temperature sulfur deactivation of SCR catalyst, which seriously affects the safe operation of denitration system. The traditional deep regeneration can remove the catalyst pollution caused by low temperature sulfur deactivation, but after regeneration, the catalyst still easily occurs low temperature sulfur deactivation phenomenon when re-entering the running environment. Sulfur compounds are easy to form metal sulfides with various metal salts, causing the blockage of pore. In the traditional active material loading method, the vanadium content reaches a certain limit, and it is difficult to further increase the concentration, so it is necessary to introduce additional metal materials to realize the loading of active materials. Therefore, it is of great significance to develop a kind of reagent for denitration catalyst sulfur resistance regeneration. SUMMARY

[0004] The present application is based on the discovery and understanding of the inventors on the following facts and problems: the particularity of non-electricity industry flue gas treatment process is easy to cause low temperature sulfur deactivation of SCR catalyst, which seriously affects the safe operation of denitration system. The traditional deep regeneration can remove the catalyst pollution caused by low temperature sulfur deactivation, but after regeneration, the catalyst still easily occurs low temperature sulfur deactivation phenomenon when re-entering the running environment.

[0005] The present application aims to at least solve one of the technical problems in the related art. To this end, the embodiments of the present application propose a kind of denitration catalyst sulfur resistance regeneration reagent and denitration catalyst regeneration method, the denitration catalyst sulfur resistance regeneration reagent includes pre-washing reagent for ash softening, cleaning and pore recovery and active loading reagent for active component loading, which can better restore specific surface area, better remove ash in pore surface and micropore, and the poisoning phenomenon of sulfur compounds and the enrichment phenomenon of alkali metal basically disappear.

[0006] The embodiment of the present application provides a kind of denitration catalyst sulfur resistance regeneration reagent, comprising: pre-cleaning reagent and active load reagent;

[0007] Wherein, pre-cleaning reagent includes: citric acid 1-5%, triethanolamine 0.2-2%, sulfuric acid 0.05-5%, alkyl glycoside 0.1-2%, dodecyl trimethyl ammonium bromide 0.3-4%, the rest is water, by mass;

[0008] Active load reagent includes: cerium nitrate 0.1-2%, ammonium molybdate 0.2-2%, vanadium salt 3-5%, tungsten salt 1-5%, sulfuric acid 0.1-2%, citric acid 0.1-1%, JFC penetrant 0.1-0.3%, the rest is water, by mass.

[0009] The denitration catalyst sulfur resistance regeneration reagent of the embodiment of the present application has the advantages and technical effects that: the most critical process in the sulfur resistance regeneration process is the recovery of the pore and the loading of the active component, the denitration catalyst sulfur resistance regeneration reagent includes the pre-cleaning reagent for ash softening, cleaning and pore recovery and the active load reagent for active component loading, can better recover the specific surface area, better remove the ash accumulated on the pore surface and in the micropore, and the poisoning phenomenon of sulfur substances and the alkali enrichment phenomenon basically disappear.

[0010] In the embodiment of the present application, citric acid is used as the reaction raw material for pore expansion on the basis of sulfuric acid stabilizing pH, for the recovery of specific surface area, and citric acid and sulfuric acid cooperate, which can maintain performance for a longer time compared with using citric acid or sulfuric acid or other acids alone. Triethanolamine has a certain pore expansion effect, and small organic molecules fill the internal pores, which can be naturally decomposed in the later heating process, assisting citric acid and the like to recover the specific surface area. Alkyl glycoside and dodecyl trimethyl ammonium bromide are added in small amounts for solution penetration and accelerate the softening and loosening of the cemented ash. Among them, alkyl glycoside has good hydrophilic performance as a surfactant, can be compounded with dodecyl trimethyl ammonium bromide to produce a synergistic effect, the generated foam is delicate, which can assist the softening and loosening of ash, and can normally operate under acidic conditions; dodecyl trimethyl ammonium bromide can have an amphiphilic structure, can better wet the surface of ash, and is easy to be compounded with multiple surfactants; compared with other surfactants, alkyl glycoside and dodecyl trimethyl ammonium bromide are used in combination, which can increase the pore expansion and cleaning effect.

[0011] In the embodiment of the present application, the introduction of cerium increases the low-temperature performance of the catalyst and strengthens the low-temperature activity. Mo doping provides a combined sacrificial site for SO2 and has a certain effect of resisting sulfur. Vanadium salt and tungsten salt are conventional supplements of active components and are used to supplement the active components lost in the cleaning process. Sulfuric acid and citric acid are used to control pH and ensure the stability of the solution. The combination of sulfuric acid and citric acid can maintain weak acidity, promote metal loading, and citric acid infiltrates into the pores of the catalyst. After heating, it will decompose to generate tiny carbon dioxide bubbles for pore expansion, and sulfuric acid as an acid supplement can maintain pH. The JFC penetrant can increase the infiltration performance of the loading solvent, which is beneficial to internal penetration.

[0012] In some embodiments, in the pre-cleaning agent, the alkyl glycoside includes at least one of APG-06, APG-08, and APG-1214;

[0013] And / or, in the active loading agent, the vanadium salt includes at least one of ammonium metavanadate, vanadyl oxalate, vanadyl sulfate, and sodium metavanadate;

[0014] And / or, in the active loading agent, the tungsten salt includes at least one of ammonium tungstate, magnesium tungstate, calcium tungstate, and potassium tungstate;

[0015] And / or, in the active loading agent, the JFC penetrant includes at least one of JFC-1, JFC-2, and JFC-E.

[0016] The embodiment of the present application provides a denitration catalyst regeneration method, which adopts the denitration catalyst sulfur-resistant regeneration agent provided by the embodiment of the present application, and includes the following steps:

[0017] (1) Dry and wet ashing is performed on the catalyst module;

[0018] (2) The catalyst module treated in step (1) is immersed in a dilute solution of the pre-cleaning agent for pre-cleaning;

[0019] (3) The catalyst module treated in step (2) is immersed in a dilute solution of the cleaning agent for cleaning;

[0020] (4) The catalyst module treated in step (3) is immersed in a dilute solution of the cleaning agent for cleaning under ultrasonic conditions;

[0021] (5) The catalyst module treated in step (4) is immersed in water for cleaning, and then dried after cleaning;

[0022] (6) The catalyst module treated in step (5) is immersed in a dilute solution of the active loading agent, and then dried and calcined after being taken out, to obtain a regenerated denitration catalyst.

[0023] The most critical process in the anti-sulfur regeneration process in the embodiment of the present application is the recovery of the pores and the loading of the active components. The anti-sulfur regeneration agent for the denitration catalyst of the present application includes pre-cleaning agents for softening, cleaning and pore recovery and active loading agents for active component loading, which can better recover the specific surface area, better remove the accumulated ash on the pore surface and inside the micropores, and basically eliminate the poisoning phenomenon of sulfur substances and the alkali metal enrichment phenomenon.

[0024] In the embodiment of the present application, the accumulated ash in the flue gas channel is removed and loosened by dry ash removal and wet ash removal, then immersed in the pre-cleaning agent for pre-cleaning, softening and cleaning the dirt, then cleaned in the cleaning agent, ultrasonic cleaned and rinsed in water to fully remove the accumulated ash, and finally loaded with active components in the active loading agent to improve the activity of the denitration catalyst, realizing anti-sulfur regeneration and activity recovery.

[0025] In some embodiments, the pre-cleaning time in step (2) is 0.5-3h;

[0026] And / or, the mass percentage concentration of the pre-cleaning agent in the diluent of the pre-cleaning agent is 1-20%;

[0027] And / or, the pre-cleaning is carried out under the condition of compressed air bubbling.

[0028] In some embodiments, the immersion time in step (6) is 15-45min;

[0029] And / or, the mass percentage concentration of the active loading agent in the diluent of the active loading agent is 5-30%.

[0030] In some embodiments, the drying temperature in step (6) is 100-140℃; and the drying time is 1-3h;

[0031] And / or, the calcination temperature is 350-450℃; and the calcination time is 2-6h.

[0032] In some embodiments, the dry ash removal step in step (1) includes: first removing the floating ash on the surface of the catalyst module, and then using compressed air to blow off the ash;

[0033] And / or, the wet ash removal step includes: spraying deionized water to the catalyst module treated by dry ash removal to remove the ash.

[0034] In some embodiments, the cleaning agent in step (3) includes: coconut oil fatty acid diethanolamide 0.2-10%, alkyl glycoside 1-20%, JFC penetrant 0.1-1wt%, sodium carbonate 0.2-3wt%, sulfuric acid 0.2-6wt%, and the rest is water, by mass.

[0035] and / or, the mass percentage concentration of the cleaning agent in the diluent of the cleaning agent is 2-20%;

[0036] and / or, the cleaning time is 60-120 min.

[0037] and / or, the cleaning is performed under compressed air bubbling conditions.

[0038] In some embodiments, in the step (4), the mass percentage concentration of the cleaning agent in the diluent of the cleaning agent is 2-20%;

[0039] and / or, the cleaning time is 10-60 min.

[0040] In some embodiments, in the step (5), the cleaning time is 10-50 min.

[0041] and / or, the cleaning is performed under compressed air bubbling conditions. DETAILED DESCRIPTION

[0042] Embodiments of the present application are described in detail below, which are exemplary and intended to explain the present application, and cannot be understood as a limitation of the present application.

[0043] The denitration catalyst anti-sulfur regeneration agent of the embodiment of the present application comprises: a pre-cleaning agent and an active component loading agent; wherein the pre-cleaning agent comprises: 1-5% of citric acid, 0.2-2% of triethanolamine, 0.05-5% of sulfuric acid, 0.1-2% of alkyl glycoside, 0.3-4% of dodecyl trimethyl ammonium bromide, and the rest is water, by mass; the active component loading agent comprises: 0.1-2% of cerium nitrate, 0.2-2% of ammonium molybdate, 3-5% of vanadium salt, 1-5% of tungsten salt, 0.1-2% of sulfuric acid, 0.1-1% of citric acid, 0.1-0.3% of JFC penetrant, and the rest is water, by mass.

[0044] The denitration catalyst anti-sulfur regeneration agent of the embodiment of the present application comprises the pre-cleaning agent for ash softening, cleaning and pore recovery and the active component loading agent for active component loading, which can better restore the specific surface area, better remove the ash accumulated on the pore surface and inside the micropore, and the poisoning phenomenon of sulfur substances and the alkali metal enrichment phenomenon basically disappear.

[0045] In the embodiment of the present application, on the basis of sulfuric acid stabilizing pH, citric acid is used as a reaction raw material for hole expansion, and is used for the recovery of specific surface area, citric acid and sulfuric acid cooperate, and the performance is maintained for a long time compared with using citric acid or sulfuric acid or other acids alone. Triethanolamine has a certain hole expansion effect, and small molecule organic substances are filled in the internal pore channel, which can be naturally decomposed in the later heating process, and assists citric acid and the like to realize the recovery of specific surface area. Alkyl glycoside and dodecyl trimethyl ammonium bromide are added in a small amount for solution penetration, and accelerate the softening and loosening of the cemented ash dirt. Among them, the alkyl glycoside has good hydrophilic performance as a surfactant, can be compounded with dodecyl trimethyl ammonium bromide to produce a synergistic effect, the generated foam is delicate, can assist the softening and loosening of the ash dirt, and can normally operate under acidic conditions; dodecyl trimethyl ammonium bromide can have an amphiphilic structure, can better wet the surface of the ash dirt, and is easy to be compounded with multiple surfactants; compared with other surfactants, the combination of alkyl glycoside and dodecyl trimethyl ammonium bromide can increase the hole expansion cleaning effect.

[0046] In the embodiment of the present application, the introduction of cerium increases the low-temperature performance of the catalyst and strengthens the low-temperature activity. Mo doping provides a combined sacrifice site for SO2 and has a certain sulfur resistance effect. Vanadium salt and tungsten salt are used as conventional supplements of active components to supplement the active components lost in the cleaning process. Sulfuric acid and citric acid are used to control pH to ensure the stability of the solution. The combination of sulfuric acid and citric acid can maintain weak acidity, promote metal loading, and citric acid infiltrates into the pores of the catalyst. After heating, it will decompose to generate tiny carbon dioxide bubbles for hole expansion, and sulfuric acid as an acid supplement can maintain pH. JFC penetrant can increase the infiltration performance of the loading solvent, which is beneficial to internal penetration.

[0047] In some embodiments, the sulfur-resistant regeneration agent for the denitration catalyst further comprises a cleaning agent, and the cleaning agent comprises: coconut oil fatty acid diethanolamide 0.2-10%, alkyl glycoside 1-20%, JFC penetrant 0.1-1wt%, sodium carbonate 0.2-3wt%, sulfuric acid 0.2-6wt%, and the rest is water.

[0048] In some embodiments, the alkyl glycoside in the pre-cleaning agent comprises at least one of APG-06, APG-08, and APG-1214.

[0049] And / or, the vanadium salt in the active loading agent comprises at least one of ammonium metavanadate, vanadyl oxalate, vanadyl sulfate, and sodium metavanadate.

[0050] And / or, the tungsten salt in the active loading agent comprises at least one of ammonium tungstate, magnesium tungstate, calcium tungstate, and potassium tungstate.

[0051] And / or, in the active load medicament, the JFC penetrant includes at least one of JFC-1, JFC-2, JFC-E.

[0052] The method for regenerating the denitration catalyst according to the embodiment of the application adopts the sulfur-resistant regeneration medicament for the denitration catalyst according to the embodiment of the application, and comprises the following steps:

[0053] (1) Dry and wet ashing is performed on the catalyst module;

[0054] (2) The catalyst module treated in step (1) is immersed in a dilute solution of the pre-cleaning medicament for pre-cleaning;

[0055] (3) The catalyst module treated in step (2) is immersed in a dilute solution of the cleaning medicament for cleaning;

[0056] (4) The catalyst module treated in step (3) is immersed in a dilute solution of the cleaning medicament for cleaning under ultrasonic conditions;

[0057] (5) The catalyst module treated in step (4) is immersed in water for cleaning, and then dried;

[0058] (6) The catalyst module treated in step (5) is immersed in a dilute solution of the active load medicament, and then dried and calcined after being taken out, to obtain the regenerated denitration catalyst.

[0059] In the embodiment of the application, the most critical process in the sulfur-resistant regeneration process is the recovery of the pores and the loading of the active components. The sulfur-resistant regeneration medicament for the denitration catalyst according to the application comprises the pre-cleaning medicament for softening, cleaning and recovering the pores and the active load medicament for loading the active components, which can better recover the specific surface area, better remove the accumulated ash on the pore surface and in the micropores, and basically eliminate the poisoning phenomenon of sulfur substances and the enrichment phenomenon of alkali metals.

[0060] In the embodiment of the application, the ash accumulated in the flue is removed and loosened by dry and wet ashing, and then the pre-cleaning medicament is used for pre-cleaning to soften and clean the dirt. Then, the cleaning medicament is used for cleaning, ultrasonic cleaning and rinsing in water to fully remove the accumulated ash. Finally, the active components are loaded in the active load medicament to improve the activity of the denitration catalyst, so that the sulfur-resistant regeneration and the activity recovery are realized.

[0061] In some embodiments, in step (2), the pre-cleaning time is 0.5-3h, specifically, for example, 0.5h, 1h, 2h, 3h; and / or, the mass percentage concentration of the pre-cleaning agent in the diluent of the pre-cleaning agent is 1-20%, specifically, for example, 1%, 3%, 5%, 10%, 15%, 20%; and / or, the pre-cleaning is performed under compressed air bubbling, preferably, compressed air bubbling is used at the bottom of the cleaning tank. In the embodiments of the present application, the preferred pre-cleaning process is beneficial to enhancing the cleaning effect and saving energy. If the pre-cleaning time is too short, the ash is not infiltrated and softened; if the time is too long, the construction period is prolonged and the energy consumption is increased.

[0062] In some embodiments, before step (3), the catalyst module treated in step (2) is rinsed with water, preferably, the water is desalted water.

[0063] In some embodiments, in step (6), the immersion time is 15-45min, preferably, 30min; and / or, the mass percentage concentration of the active load agent in the diluent of the active load agent is 5-30%, specifically, for example, 5%, 10%, 15%, 20%, 25%, 30%; the timing starts from the immersion of the active load agent from the windward side of the catalyst module, i.e. the top end of the catalyst module. In the embodiments of the present application, the preferred process of immersing the active load agent can realize uniform loading and penetration into the internal pores of the catalyst.

[0064] In some embodiments, in step (6), the drying temperature is 100-140℃, preferably, 120℃; the drying time is 1-3h, preferably, 2h; and / or, the calcination temperature is 350-450℃, preferably, 400℃; the calcination time is 2-6h, preferably, 4h. In the embodiments of the present application, the active substance needs to be converted at a certain temperature, and the preferred drying and calcination process is beneficial to improving the activity of the catalyst with minimum energy consumption and time cost.

[0065] In some embodiments, in step (1), the dry ash removal step includes: first removing the floating ash on the surface of the catalyst module, and then using compressed air to blow and remove the ash; specifically, for example, manually removing the floating ash on the outer surface of the catalyst module frame, placing the catalyst module in the automatic ash blowing equipment room, and automatically removing the accumulated ash in the catalyst unit flow channel with compressed air; preferably, placing the catalyst module horizontally, and blowing and sweeping the catalyst unit one by one from the windward side and the leeward side of the catalyst module; the area where the flying ash is carried back is judged as the accumulated ash blocking the flue gas flow channel. With the flue gas flow channel as the axis, the nozzle is slightly shaken left and right by 10°, until no flying ash is splashed back.

[0066] In some embodiments, in the step (1), the wet ash removal step comprises: spraying deionized water to the catalyst module after dry ash removal treatment for rinsing ash removal; specifically, for example, moving the catalyst module to a regeneration spray system, using a high-pressure water gun to spray deionized water for preliminary cleaning, and after finishing, manually rinsing the catalyst with the high-pressure water gun for ash removal; preferably, judging the flue gas flow passage to be blocked by ash accumulation by visual observation or encountering the area where water splashes back, and slightly swaying the high-pressure water gun by 10° left and right of the axis connected by the flue gas flow passage and the high-pressure water gun until the passage is completely unblocked; if the ash accumulation is hard, then continuously rinsing for at least 30 seconds to soften the ash accumulation. In the embodiments of the present application, the catalyst is manually rinsed with the high-pressure water gun for ash removal, which removes all windward surface and shell ash accumulation, removes most of the loose ash accumulation or blockage in the flue gas flow passage, and removes and loosens part of the hard ash accumulation in the flue gas flow passage.

[0067] In some embodiments, in the step (3), the cleaning agent comprises: coconut oil fatty acid diethanolamide 0.2-10%, alkyl glycoside 1-20%, JFC penetrant 0.1-1wt%, sodium carbonate 0.2-3wt%, sulfuric acid 0.2-6wt%, and the rest is water; preferably, the cleaning agent comprises: coconut oil fatty acid diethanolamide 5%, alkyl glycoside 2%, JFC penetrant 0.1wt%, sodium carbonate 1wt%, sulfuric acid 1wt%, and the rest is water; preferably, the alkyl glycoside comprises at least one of APG-06, APG-08, and APG-1214; the JFC penetrant comprises at least one of JFC-1, JFC-2, and JFC-E; and / or, the mass percentage concentration of the cleaning agent in the diluent of the cleaning agent is 2-20%, specifically, for example, 2%, 3%, 5%, 10%, 15%, or 20%; and / or, the cleaning time is 60-120min, specifically, for example, 60min, 90min, or 120min; and / or, the cleaning is carried out under the condition of compressed air bubbling with the liquid surface being higher than the upper surface of the module. In the embodiments of the present application, by using the preferred cleaning agent and cleaning process, the ash cleaning effect of the catalyst is further improved, and energy consumption is reduced.

[0068] In some embodiments, in the step (4), the mass percentage concentration of the cleaning agent in the diluent of the cleaning agent is 2-20%, specifically, for example, 2%, 3%, 5%, 10%, 15%, or 20%; and / or, the cleaning time is 10-60min, specifically, for example, 10min, 20min, 30min, 40min, 50min, or 60min; and the liquid surface is higher than the upper surface of the module. In the embodiments of the present application, by using the preferred ultrasonic cleaning process, the ash cleaning effect of the catalyst is further improved, and energy consumption is reduced.

[0069] In some embodiments, in the step (5), the time for the rinsing is 10-50 min, in particular, for example, 10 min, 20 min, 30 min, 40 min, 50 min; and / or, the rinsing is performed under the condition of compressed air bubbling; the liquid surface is higher than the upper surface of the module. In the embodiments of the present application, the rinsing with clean water is beneficial to remove the surface residues.

[0070] In some embodiments, in the step (5), the temperature rising rate for the drying is not more than 6℃ / min; the temperature for the drying is 200-240℃, preferably, 220℃; the temperature falling rate for the drying is not more than 6℃ / min.

[0071] The present application is described below with reference to specific embodiments, it should be noted that these embodiments are merely descriptive, and do not limit the present application in any way.

[0072] Embodiment 1:

[0073] A certain power plant in-service denitration catalyst, after testing, there are ash deposition, channel blockage and other conditions, and there are more serious ammonium bisulfate poisoning and slight alkali metal poisoning, the channel ash deposition is in the state of sticky and hard.

[0074] The regeneration method for the denitration catalyst includes the following steps:

[0075] (1) dry and wet ash removal is performed on the catalyst module;

[0076] (2) the catalyst module treated in the step (1) is moved to a desalted water pool to be immersed in a dilute solution of a pre-cleaning agent for compressed air bubbling pre-cleaning, and the pre-cleaning is performed for 2 hours; the pre-cleaning agent includes: 3% citric acid, 1% triethanolamine, 2% sulfuric acid, 1% alkyl polyglycoside (APG-06), 2% dodecyl trimethyl ammonium bromide, and the rest is water, by mass; the mass percentage concentration of the pre-cleaning agent in the dilute solution of the pre-cleaning agent is 10%;

[0077] (3) the catalyst module treated in the step (2) is immersed in a dilute solution of a cleaning agent for compressed air bubbling cleaning, and the cleaning time is 1 hour; the cleaning agent includes: 5% coconut oil fatty acid diethanolamide, 2% alkyl polyglycoside (APG-06), 0.1wt% JFC penetrant (JFC-1), 1wt% sodium carbonate, 1wt% sulfuric acid, and the rest is water, by mass; the mass percentage concentration of the cleaning agent in the dilute solution of the cleaning agent is 5%;

[0078] (4) the catalyst module treated in the step (3) is moved to an ultrasonic tank to be immersed in a dilute solution of a cleaning agent for cleaning under ultrasonic condition, and the ultrasonic treatment process lasts for 30 minutes; the mass percentage concentration of the cleaning agent in the dilute solution of the cleaning agent is 5%.

[0079] (5) The catalyst module after step (4) is moved to a water tank and immersed in water for compressed air bubble rinsing, with a rinsing time of 30 min. The cleaned catalyst is pushed into a drying oven, and the drying program is started. The drying temperature rise rate is not more than 6°C / min. When the oven is completely heated to 220°C, the temperature is kept constant for drying. After the temperature keeping drying program is completed, the temperature is lowered at a rate not exceeding 6°C / min;

[0080] (6) The catalyst module after step (5) is immersed in a dilute solution of active load medicament for 30 min. After taking out, the catalyst module is transferred into a calcination furnace. The furnace is completely heated to 120°C, and then the temperature is maintained for 2 h for drying. Then the temperature is continuously raised to 400°C, and then maintained for 4 h for calcination to obtain a regenerated denitration catalyst. The active load medicament includes, by weight: cerium nitrate 1%, ammonium molybdate 2%, ammonium metavanadate 3%, ammonium tungstate 1%, sulfuric acid 1%, citric acid 0.5%, JFC penetrant (JFC-1) 0.2%, and the rest is water. The mass percentage concentration of the active load medicament in the dilute solution of the active load medicament is 10%.

[0081] Example 2:

[0082] A certain power plant in-service denitration catalyst was detected to have accumulated ash, pore blockage, and more serious ammonium bisulfate poisoning and slight alkali metal poisoning. The accumulated ash in the pores was in a state of sticky and hard.

[0083] The regeneration method for the denitration catalyst includes the following steps:

[0084] (1) The catalyst module is subjected to dry ash removal and wet ash removal;

[0085] (2) The catalyst module after step (1) is moved to a desalination tank and immersed in a dilute solution of pre-cleaning medicament for compressed air bubble pre-cleaning for 2 h. The pre-cleaning medicament includes, by mass: citric acid 1%, triethanolamine 2%, sulfuric acid 5%, alkyl polyglycoside (APG-08) 2%, dodecyltrimethylammonium bromide 0.3%, and the rest is water. The mass percentage concentration of the pre-cleaning medicament in the dilute solution of the pre-cleaning medicament is 5%;

[0086] (3) The catalyst module after step (2) is immersed in a dilute solution of cleaning medicament for compressed air bubble cleaning for 2 h. The cleaning medicament includes, by mass: coconut oil fatty acid diethanolamide 5%, alkyl polyglycoside (APG-08) 2%, JFC penetrant (JFC-2) 0.1 wt%, sodium carbonate 1 wt%, sulfuric acid 1 wt%, and the rest is water. The mass percentage concentration of the cleaning medicament in the dilute solution of the cleaning medicament is 10%;

[0087] (4) the catalyst module after step (3) is moved to an ultrasonic tank to immerse in a dilute solution of cleaning agent to perform cleaning under ultrasonic condition, the ultrasonic treatment process lasts for 60 minutes; the mass percentage concentration of cleaning agent in the dilute solution of cleaning agent is 10%;

[0088] (5) the catalyst module after step (4) is moved to a clean water tank to immerse in water to perform compressed air bubble rinsing, the rinsing time is 30 min, the cleaned catalyst is pushed into a drying furnace, a drying program is started, the drying temperature rising rate is not more than 6 ℃ / min, the furnace is completely heated to 220 ℃, and the temperature is kept to dry, after the temperature keeping drying program is completed, the temperature is lowered, and the temperature lowering rate is not more than 6 ℃ / min;

[0089] (6) the catalyst module after step (5) is immersed in a dilute solution of active load agent, and taken out after 30 minutes; after being taken out, the catalyst module is transferred into a calcination furnace, the furnace is completely heated to 120 ℃, and the temperature is kept to dry for 2 h; then the temperature is continuously raised, the temperature is raised to 400 ℃, and the temperature is kept to calcine for 4 h, to obtain a regenerated denitration catalyst; the active load agent includes, by weight: cerium nitrate 2%, ammonium molybdate 0.5%, vanadyl oxalate 3%, ammonium tungstate 5%, sulfuric acid 0.1%, citric acid 1%, JFC penetrant (JFC-2) 0.3%, and the rest is water; the mass percentage concentration of active load agent in the dilute solution of active load agent is 15%.

[0090] Example 3:

[0091] The in-service denitration catalyst of a certain power plant is detected to have ash accumulation, pore blockage and the like, and has relatively serious ammonium bisulfate poisoning and slight alkali metal poisoning, and the pore ash accumulation is in a state of sticky and caked.

[0092] The regeneration method for the denitration catalyst includes the following steps:

[0093] (1) the catalyst module is subjected to dry ash removal and wet ash removal;

[0094] (2) the catalyst module after step (1) is moved to a desalted water pool to immerse in a dilute solution of pre-cleaning agent to perform compressed air bubble pre-cleaning, and the pre-cleaning lasts for 2 h; the pre-cleaning agent includes, by mass: citric acid 5%, triethanolamine 0.2%, sulfuric acid 0.05%, alkyl polyglycoside (APG-1214) 0.5%, dodecyltrimethylammonium bromide 4%, and the rest is water; the mass percentage concentration of pre-cleaning agent in the dilute solution of pre-cleaning agent is 15%;

[0095] (3) The catalyst module treated in step (2) is immersed in a dilute solution of cleaning agent for compressed air bubble cleaning, and the cleaning time is 1 hour; the cleaning agent comprises: coconut oil fatty acid diethanolamide 5%, alkyl polyglycoside (APG-1214) 2%, JFC penetrant (JFC-E) 0.1wt%, sodium carbonate 1wt%, sulfuric acid 1wt%, and the rest is water, by mass; the mass percentage concentration of the cleaning agent in the dilute solution of the cleaning agent is 20%;

[0096] (4) The catalyst module treated in step (3) is moved to an ultrasonic tank and immersed in a dilute solution of cleaning agent for cleaning under ultrasonic conditions, and the ultrasonic treatment process lasts for 10 minutes; the mass percentage concentration of the cleaning agent in the dilute solution of the cleaning agent is 20%;

[0097] (5) The catalyst module treated in step (4) is moved to a clean water tank and immersed in water for compressed air bubble rinsing, and the rinsing time is 30 minutes; the cleaned catalyst is pushed into a drying oven, and the drying program is started, and the drying temperature rise rate does not exceed 6℃ / minute; when the oven is completely warmed up to 220℃, the temperature is maintained for drying; after the temperature-maintained drying program is completed, the temperature is lowered, and the temperature lowering rate does not exceed 6℃ / minute;

[0098] (6) The catalyst module treated in step (5) is immersed in a dilute solution of active load agent, and taken out after 30 minutes; after taking out, the catalyst module is transferred into a calcination furnace; after the furnace is completely warmed up to 120℃, the temperature is maintained for drying for 2h; then the temperature is continuously raised, and after the temperature is raised to 400℃, the temperature is maintained for calcination for 4h, to obtain a regenerated denitration catalyst; by weight, the active load agent comprises: cerium nitrate 0.1%, ammonium molybdate 2%, vanadyl sulfate 5%, potassium tungstate 1%, sulfuric acid 2%, citric acid 0.1%, JFC penetrant (JFC-E) 0.1%, and the rest is water; the mass percentage concentration of the active load agent in the dilute solution of the active load agent is 25%.

[0099] Comparative Example 1

[0100] The method is completely the same as that of Example 1, except that in step (2), water is used to replace the dilute solution of pre-cleaning agent, and step (6) is omitted.

[0101] Comparative Example 2

[0102] The method is completely the same as that of Example 1, except that in step (2), sulfuric acid is not contained.

[0103] Comparative Example 3

[0104] The method is completely the same as that of Example 1, except that in step (2), citric acid is not contained.

[0105] Comparative Example 4

[0106] The method of Example 1 is completely the same, except that in the step (2), no alkyl glycoside APG-06 is contained.

[0107] Comparative Example 5

[0108] The method of Example 1 is completely the same, except that in the step (2), no dodecyl trimethyl ammonium bromide is contained.

[0109] Comparative Example 6

[0110] The method of Example 1 is completely the same, except that in the step (2), dodecyl trimethyl ammonium bromide is replaced by sodium dodecyl sulfate.

[0111] Comparative Example 7

[0112] The method of Example 1 is completely the same, except that in the step (6), no sulfuric acid is contained.

[0113] Comparative Example 8

[0114] The method of Example 1 is completely the same, except that in the step (6), no citric acid is contained.

[0115] Comparative Example 9

[0116] The method of Example 1 is completely the same, except that in the step (6), no JFC penetrant is contained.

[0117] The results of the specific surface area detection of the catalyst samples of the pre-regeneration, the comparative examples and Example 1 are shown in Table 1.

[0118] Table 1 Results of the specific surface area detection

[0119]

[0120] As shown in Table 1, the specific surface area of the regenerated sample of Example 1 is higher than that of the pre-regeneration, and also higher than that of the regenerated samples in the comparative examples, which indicates that the regeneration method of the present application can better restore the specific surface area and better remove the accumulated dust on the pore surface and inside the micropores.

[0121] The results of the chemical composition detection of the catalyst samples of the pre-regeneration, the comparative examples and Example 1 are shown in Table 2.

[0122] Table 2 Results of the chemical composition detection

[0123]

[0124] As shown in Table 2, in Example 1, the contents of SO3, CaO and MgO are reduced, the poisoning phenomenon of sulfur species is basically eliminated, the ash deposition on the channel surface and inside the micropore is well removed, and the enrichment of calcium sulfate and alkali metals is cleaned.

[0125] In the present application, the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" mean that the particular feature, structure, material or characteristic being described is included in at least one embodiment or example of the present application. Illustrative appearances of the above terms in the specification are not necessarily referring to the same embodiment or example. Moreover, the described particular features, structures, materials or characteristics can be combined in any suitable manner in one or more embodiments or examples. Furthermore, the described particular features, structures, materials or characteristics can be combined in any suitable manner in one or more embodiments or examples, provided that the combination does not result in a contradictory or unfeasible specification.

[0126] Although the above embodiments have been shown and described, it should be understood by those skilled in the art that the above embodiments are exemplary and cannot be construed as limiting the present application, and any changes, modifications, replacements and variations made by those skilled in the art to the above embodiments are within the scope of the present application.

Claims

1. A sulfur-resistant regenerant for a denitration catalyst, characterized by comprising: 1) a transition metal compound, 2) a nitrogen compound, and 3) a phosphorus compound. Comprise: pre-cleaning agent, cleaning agent and active load agent; wherein the pre-cleaning agent comprises: 1-5% of citric acid, 0.2-2% of triethanolamine, 0.05-5% of sulfuric acid, 0.1-2% of alkyl glycoside, 0.3-4% of dodecyl trimethyl ammonium bromide, and the rest is water by mass; the active load agent comprises: 0.1-2% of cerium nitrate, 0.2-2% of ammonium molybdate, 3-5% of vanadium salt, 1-5% of tungsten salt, 0.1-2% of sulfuric acid, 0.1-1% of citric acid, 0.1-0.3% of JFC penetrant, and the rest is water by mass; the cleaning agent comprises: 0.2-10% of coconut oil fatty acid diethanolamide, 1-20% of alkyl glycoside, 0.1-1wt% of JFC penetrant, 0.2-3wt% of sodium carbonate, 0.2-6wt% of sulfuric acid, and the rest is water by mass; The method for regenerating denitration catalyst comprises the following steps: (1) Dry and wet ashing of the catalyst module; (2) Pre-cleaning of the catalyst module treated in step (1) by immersing it in a dilute solution of pre-cleaning agent; (3) Cleaning of the catalyst module treated in step (2) by immersing it in a dilute solution of cleaning agent; (4) Cleaning of the catalyst module treated in step (3) by immersing it in a dilute solution of cleaning agent under ultrasonic condition; (5) Cleaning of the catalyst module treated in step (4) by immersing it in water, and drying after cleaning; (6) Immersing the catalyst module treated in step (5) in a dilute solution of active load agent, and drying and calcining after taking out, to obtain regenerated denitration catalyst.

2. The sulfur-resistant regenerant for a denitration catalyst according to claim 1, characterized by, In the pre-cleaning agent, the alkyl glycoside comprises at least one of APG-06, APG-08 and APG-1214; And / or, in the active load agent, the vanadium salt comprises at least one of ammonium metavanadate, vanadyl oxalate, vanadyl sulfate and sodium metavanadate; And / or, in the active load agent, the tungsten salt comprises at least one of ammonium tungstate, magnesium tungstate, calcium tungstate and potassium tungstate; And / or, in the active load agent, the JFC penetrant comprises at least one of JFC-1, JFC-2 and JFC-E.

3. A method for regenerating a denitration catalyst, characterized by, The method for regenerating denitration catalyst comprises the following steps: (1) Dry and wet ashing of the catalyst module; (2) Pre-cleaning of the catalyst module treated in step (1) by immersing it in a dilute solution of pre-cleaning agent; (3) Cleaning of the catalyst module treated in step (2) by immersing it in a dilute solution of cleaning agent; (4) Cleaning of the catalyst module treated in step (3) by immersing it in a dilute solution of cleaning agent under ultrasonic condition; (5) Cleaning of the catalyst module treated in step (4) by immersing it in water, and drying after cleaning; (6) Immersing the catalyst module treated in step (5) in a dilute solution of active load agent, and drying and calcining after taking out, to obtain regenerated denitration catalyst.

4. The method for regenerating a denitration catalyst according to claim 3, characterized by, In step (2), the pre-cleaning time is 0.5-3h; And / or, the mass percentage concentration of the pre-cleaning agent in the diluent of the pre-cleaning agent is 1-20%; And / or, the pre-cleaning is carried out under the condition of compressed air bubbling.

5. The method for regenerating a denitration catalyst according to claim 3, wherein In the step (6), the time of the immersion is 15-45 min; And / or, the mass percentage concentration of the active load agent in the diluent of the active load agent is 5-30%.

6. The method for regenerating a denitration catalyst according to claim 3, wherein In the step (6), the temperature of the drying is 100-140℃; the time of the drying is 1-3h; And / or, the temperature of the calcination is 350-450℃; the time of the calcination is 2-6h.

7. The method for regenerating a denitration catalyst according to claim 3, wherein In the step (1), the step of the dry ash removal comprises: firstly removing the floating ash on the surface of the catalyst module, and then using compressed air to blow and remove the ash; And / or, the step of the wet ash removal comprises: spraying deionized water to the catalyst module treated by the dry ash removal to wash and remove the ash.

8. The method for regenerating a denitration catalyst according to claim 3, wherein In the step (3), the mass percentage concentration of the cleaning agent in the diluent of the cleaning agent is 2-20%; And / or, the time of the cleaning is 60-120 min; And / or, the cleaning is carried out under the condition of compressed air bubbling.

9. The method for regenerating a denitration catalyst according to claim 3, wherein In the step (4), the mass percentage concentration of the cleaning agent in the diluent of the cleaning agent is 2-20%; And / or, the time of the cleaning is 10-60 min.

10. The method for regenerating a denitration catalyst according to claim 3, wherein In the step (5), the time of the cleaning is 10-50 min; And / or, the cleaning is carried out under the condition of compressed air bubbling.

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