CN111302397B - Method and device for recovering waste denitration catalyst - Google Patents

Method and device for recovering waste denitration catalyst Download PDF

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CN111302397B
CN111302397B CN202010176116.6A CN202010176116A CN111302397B CN 111302397 B CN111302397 B CN 111302397B CN 202010176116 A CN202010176116 A CN 202010176116A CN 111302397 B CN111302397 B CN 111302397B
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silicon material
low
solid
filtrate
catalyst
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CN111302397A (en
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陈进生
苏清发
王金秀
陈衍婷
江长水
尹丽倩
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Institute of Urban Environment of CAS
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G41/00—Compounds of tungsten
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J38/00—Regeneration or reactivation of catalysts, in general
    • B01J38/02—Heat treatment
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J38/00—Regeneration or reactivation of catalysts, in general
    • B01J38/48—Liquid treating or treating in liquid phase, e.g. dissolved or suspended
    • B01J38/64—Liquid treating or treating in liquid phase, e.g. dissolved or suspended using alkaline material; using salts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J38/00—Regeneration or reactivation of catalysts, in general
    • B01J38/72—Regeneration or reactivation of catalysts, in general including segregation of diverse particles
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    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G31/00—Compounds of vanadium
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    • Y02P20/584—Recycling of catalysts

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Abstract

The invention relates to a method and a device for recovering a waste denitration catalyst, wherein the method comprises the following steps: 1) ash removal and pretreatment of the waste denitration catalyst; 2) the pretreated waste catalyst is treated by a physical separation process; 3) carrying out alkaline leaching treatment on the separated low-silicon material; 4) washing, drying and calcining the filter cake after alkaline leaching to obtain titanium dioxide; 5) and (3) respectively separating and purifying tungsten and vanadium in the filtrate to respectively obtain tungstic acid and vanadate. The invention adopts a physical separation process to separate the catalyst into a low-silicon material and a high-silicon material before alkaline leaching, overcomes the technical problems caused by impurities such as silicon, aluminum, calcium and the like in the traditional catalyst recovery process, reduces water consumption and alkali consumption, and simultaneously reduces the dosage of medicaments required by the subsequent separation and purification processes.

Description

Method and device for recovering waste denitration catalyst
Technical Field
The invention relates to the technical field of resource utilization of industrial solid wastes, in particular to a method and a device for recycling a waste denitration catalyst.
Background
Nitrogen Oxides (NO)x) Is one of the main pollutants causing haze and photochemistry, and harms human health. Along with the national emphasis on the ecological civilization construction, the government increasingly emphasizes the industrial source NOxPollution source treatment and ultra-clean discharge become trends,require NO from industrial flue gasxThe discharge concentration is less than 50mg/Nm3. The selective catalytic reduction method is currently industrial flue gas NOxThe mainstream technology of control utilizes ammonia or other reducing agents to reduce nitrogen oxides into nitrogen and water under the action of a catalyst. Wherein, the catalyst is the technical core and the consumable of the system operation. The catalyst generally takes titanium dioxide as a carrier, tungsten trioxide as a catalytic assistant and vanadium pentoxide as an active component. The service life of the catalyst is generally 3-4 years, and then the activity of the catalyst cannot meet the denitration efficiency requirement due to poisoning, loss of active components, blockage or reduction of mechanical strength and the like, so that the catalyst becomes a waste catalyst. Since the waste catalyst contains high heavy metal elements and is classified as hazardous solid waste (HW49), the method for recycling the waste denitration catalyst is very important, and if the waste denitration catalyst is not properly disposed, environmental pollution and resource waste are caused.
At present, the main process steps of the disclosed wet-process alkaline leaching recovery method of the waste denitration catalyst comprise: cleaning, pulverizing, alkaline leaching, separating and purifying, etc.
For example, chinese patent application CN110578058A discloses a method for recovering titanium, tungsten, vanadium and silicon from waste denitration catalysts of coal-fired flue gas, which comprises the steps of cleaning ash of the waste denitration catalysts, crushing the ash to particles smaller than 200 meshes, impregnating the ash with 30-40 wt.% sodium hydroxide or potassium hydroxide solution, adjusting the pH of the leachate with hydrochloric acid or sulfuric acid, removing silica impurities in the form of silicic acid, and then gradually separating tungsten and vanadium, thereby realizing resource utilization of the waste denitration catalysts.
Chinese patent application CN109536722A discloses a method for recovering and recycling waste denitration catalyst, which comprises the steps of pre-treating the waste denitration catalyst to remove ash, crushing into block products, grinding into powder, adopting sodium hydroxide ultrasonic wave to strengthen alkaline leaching, liquid-solid separation, adding hydrochloric acid to remove silicon, aluminum and the like, ion exchange, desorption, evaporative crystallization, and recycling to produce new catalyst.
Chinese patent CN 107419104B discloses a comprehensive recovery method of a spent denitration catalyst, which comprises the steps of crushing, grinding, alkaline leaching, acid precipitation, extraction and the like, and the method adopts an extraction/back extraction process in order to improve the product purity and reduce the influence of impurities such as silicon, aluminum and the like.
Therefore, when the denitration catalyst is produced, in order to improve the mechanical strength of a product, a certain amount of glass fiber is usually added into a raw material, and the main chemical components of the glass fiber, namely silicon dioxide, aluminum oxide and calcium oxide, usually account for 3-10 wt.% of the catalyst, are almost equivalent to the contents of target extracted chemical components, namely vanadium pentoxide and tungsten trioxide, and are even higher. Therefore, the processes of impurity removal, separation and purification after alkaline leaching become complex, the economy is poor, and the method is difficult to accord with the green development concept advocated by the state.
Disclosure of Invention
The invention aims to solve the problem of complex impurity removal, separation and purification processes after alkaline leaching in the existing waste denitration catalyst recovery technology, and provides a method for recovering a waste denitration catalyst.
When vanadium and tungsten are leached from the waste denitration catalyst by using lye, some impurities which are not recovery targets, such as silicon, aluminum, calcium and the like, are also transferred into the solution, and in order to obtain a pure solution containing vanadium and tungsten recovery target substances, the impurities must be purified first. At present, the purification of silicon and aluminum impurities generally adopts methods such as a chemical precipitation method, a solvent extraction method, an ion exchange method and the like, and if the impurity content in a solution is high, a large amount of precipitation reagent, an extracting agent or ion exchange resin and the like are consumed in the impurity removal step.
The invention also protects a waste denitration catalyst recovery device, the waste denitration catalyst is recovered by using the waste denitration catalyst recovery device, the process is shortened compared with the traditional recovery device, and the production efficiency is high.
In the invention, the ash removal in the step 1) is carried out on the waste catalyst by utilizing compressed air or high-pressure water to carry out integral ash removal treatment on the waste catalyst so as to prevent dust impurities deposited by the waste catalyst from entering a subsequent leaching process, and then the dust impurities are crushed and sieved through pretreatment so as to meet the requirement of a physical separation step. Preferably, the pre-treated catalyst particles have a particle size of less than 10 mm.
The physical separation process of the step 2) comprises the following steps: the catalyst is broken up by utilizing the jet milling principle, large particles are gradually pulverized into fine particles under repeated high-speed impact and collision, and the glass fiber still keeps larger particle size due to the characteristics of special fibrous shape and higher toughness. The powder enters the grading chamber along with the airflow, the grading rotor rotates at a high speed, under the combined action of centrifugal force and centripetal force, the coarse particles return to the airflow crushing chamber, and the fine particles enter the catcher along with the airflow and are collected to respectively obtain low-silicon materials and high-silicon materials. Preferably, the mass content of silicon dioxide in the high-silicon material is more than 20%, the mass content of silicon dioxide in the low-silicon material is less than 1.0%, and the 45-micron sieve passing rate of the low-silicon material is more than 95%. Through the separation of the high-silicon material and the low-silicon material, the pre-separation of the recovered target element and the impurity element is achieved, and the purposes of impurity removal, separation and simplification of purification after alkaline leaching are achieved.
The preferable process of alkaline leaching in the step 3) is as follows: the mass ratio of the solid alkali to the low-silicon material is 0.5-2.0, the concentration of the ore pulp is 5% -25%, the alkaline leaching temperature is 60-130 ℃, the reaction time is 1-4 hours, and solid-liquid separation is carried out to obtain filter residue 1 and filtrate 1. And fully washing and drying the filter residue 1 to obtain the titanium dioxide. The basic leaching realizes the separation of titanium element from tungsten and vanadium, and the principle is that titanium dioxide is insoluble in alkali liquor under the optimal process conditions, and vanadium and tungsten can form vanadate and tungstate with the alkali liquor respectively, so the basic leaching process is very important, for example, the mass ratio of solid alkali to low-silicon material is 0.5-2.0, the mass ratio of solid alkali to low-silicon material is lower than 0.5, the recovery rate of vanadium and tungsten is low, the mass ratio of high-silicon material to low-silicon material is higher than 2.0, the subsequent impurity removal and purification difficulty is increased, and the cost is increased.
The separation and purification of the step 5) are as follows: adding an oxidant into the filtrate 1, adding an inorganic acid after an oxidation reaction, carrying out solid-liquid separation to obtain filter residue 2 and filtrate 2, adjusting the pH value of the filtrate 2 to 8-10, then adding a calcium salt to precipitate vanadium, and carrying out solid-liquid separation to obtain filter residue 3 and filtrate 3. The separation of tungsten and vanadium is realized in the process, the vanadium exists in a high valence state ion by adding the oxidant, the solubility is improved, so that tungstic acid precipitate is formed under the action of inorganic acid, the separation of vanadium and tungsten is realized, then calcium salt is further added to generate calcium vanadate precipitate, the separation of vanadium from the solution is realized, and finally calcium vanadate is obtained.
The specific scheme is as follows:
a method for recovering a waste denitration catalyst comprises the following steps:
step 1) carrying out ash removal and pretreatment on a waste denitration catalyst;
step 2) treating the pretreated catalyst by adopting a physical separation process to obtain a low-silicon material and a high-silicon material;
step 3) carrying out alkaline leaching on the separated low-silicon material, and filtering to obtain a filtrate 1 and a filter residue 1;
step 4) washing, drying and calcining the filter residue 1 obtained in the step 3) to obtain titanium dioxide;
and 5) separating and purifying tungsten and vanadium in the filtrate 1 obtained in the step 3) to respectively obtain tungstic acid and vanadate.
Further, the ash removal mode in the step 1) is to clean the attached dust of the catalyst by compressed air or high-pressure water, the pretreatment is coarse crushing, and the particle size of the coarse crushed particles is less than 10 mm.
Further, in the step 2), the physical separation process is as follows: the catalyst is broken up by using the jet milling principle and then separated by a grading device to obtain a low-silicon material and a high-silicon material.
Furthermore, the catalyst is broken up by utilizing the jet milling principle, large particles are gradually milled into fine particles under repeated high-speed impact and collision, and the glass fiber still maintains larger particle size due to the characteristics of special fibrous shape and higher toughness; the powder formed after the catalyst is scattered enters a grading chamber along with the airflow, the grading rotor rotates at a high speed, under the combined action of centrifugal force and centripetal force, coarse particles return to an airflow crushing chamber, fine particles enter a catcher along with the airflow and are collected to respectively obtain a low silicon material and a high silicon material, the low silicon material is positioned in the catcher, and the high silicon material is positioned in the airflow crushing chamber.
Further, in the step 2), the mass content of silicon dioxide in the high-silicon material is more than 20%, the mass content of silicon dioxide in the low-silicon material is less than 1.0%, and the 45-micron sieve passing rate of the low-silicon material is more than 95%;
optionally, the high-silicon material is recycled for preparing a fresh denitration catalyst, or silicic acid is obtained after alkaline leaching and pH adjustment;
optionally, in the step 3), the alkaline leaching is performed by using solid alkali and the low-silicon material in a mass ratio of 0.5-2.0, the mass concentration of ore pulp is 5-25%, the temperature of the alkaline leaching is 60-130 ℃, and the reaction time is 1-4 hours.
Further, the solid alkali is one or a combination of two of sodium hydroxide and potassium hydroxide in any proportion.
Further, the method for separating and purifying tungsten and vanadium in the step 5) comprises the following steps: adding an oxidant into the filtrate 1, performing oxidation reaction, adding an inorganic acid, performing solid-liquid separation to obtain a filter residue 2 and a filtrate 2, adjusting the pH of the filtrate 2 to 8-10, adding a calcium salt into the filtrate 2, and performing solid-liquid separation to obtain a filter residue 3 and a filtrate 3; and the filter residue 2 contains tungsten element, and the filter residue 3 contains vanadium element, so that the separation of tungsten and vanadium is realized.
Further, the inorganic acid is one or any combination of two of hydrochloric acid and sulfuric acid;
optionally, the filter residue 2 is tungstic acid, the filter residue 3 is vanadate, and the calcium salt is calcium chloride.
The invention also discloses a waste denitration catalyst recovery device, which is used for recovering the waste denitration catalyst by using the waste denitration catalyst recovery method and comprises a waste catalyst storage bin, an ash removal device, a pretreatment device, a physical separation device, a high-silicon material storage bin, a low-silicon material storage bin, an alkaline leaching device, a first solid-liquid separation device, a tungsten precipitation device, a second solid-liquid separation device, a vanadium precipitation device and a third solid-liquid separation device;
the ash cleaning device is connected with the pretreatment device, the pretreatment device is connected with the physical separation device, the physical separation device separates high-silicon materials to be conveyed to the high-silicon material storage bin, and the physical separation device separates low-silicon materials to be conveyed to the low-silicon material storage bin;
the low-silicon material storage bin is connected with the alkaline leaching device, the alkaline leaching device is connected with the first solid-liquid separation device, and filtrate 1 and filter residue 1 are obtained through solid-liquid separation; the filtrate 1 is conveyed to the tungsten precipitation device, is conveyed to the second solid-liquid separation device after being oxidized and subjected to tungsten precipitation reaction by adding acid, and is subjected to solid-liquid separation to obtain a filtrate 2 and a filter residue 2; and conveying the filtrate 2 to the vanadium precipitation device, conveying to the third solid-liquid separation device after vanadium precipitation by calcium salt, and performing solid-liquid separation to obtain filtrate 3 and filter residue 3.
Further, the pretreatment device is a coarse crushing device;
optionally, the physical separation device comprises a jet mill and a classifier.
Has the advantages that: compared with the prior art, the invention has the following characteristics:
1. the invention initiates the pretreatment of the waste catalyst by using the jet milling principle, effectively separates the waste catalyst into a low-silicon material and a high-silicon material before alkaline leaching, and prevents impurity elements such as silicon, aluminum, calcium and the like from entering a post-stage alkaline leaching process, thereby reducing the dosage of medicaments in the alkaline leaching and purification stages.
2. The invention provides a multi-stage physical pretreatment impurity removal scheme, can simplify the separation and purification steps after alkaline leaching, has simple process, no high-pressure condition and low cost, and is more suitable for industrial application.
3. The physical separation provided by the invention realizes the effective enrichment of glass fiber-high silicon material, and can be used for preparing silicic acid or directly reused for preparing fresh catalyst.
4. The recovery device for the waste denitration catalyst provided by the invention is short in process, high in production efficiency and good in industrial application prospect.
Drawings
In order to illustrate the technical solution of the present invention more clearly, the drawings will be briefly described below, and it is apparent that the drawings in the following description relate only to some embodiments of the present invention and are not intended to limit the present invention.
FIG. 1 is a schematic process flow diagram provided in one embodiment 1 of the present invention.
Detailed Description
Preferred embodiments of the present invention will be described in more detail below. While the following describes preferred embodiments of the present invention, it should be understood that the present invention may be embodied in various forms and should not be limited by the embodiments set forth herein. The examples do not specify particular techniques or conditions, and are performed according to the techniques or conditions described in the literature in the art or according to the product specifications. The reagents or instruments used are conventional products which are commercially available, and are not indicated by manufacturers. In the following examples, "%" means weight percent, unless otherwise specified.
The waste denitration catalyst adopted by the embodiment is derived from a power plant in Zhejiang, and the main elements of the waste denitration catalyst comprise the following components in percentage by mass: TiO 22 84.04％，V2O50.77％，WO32.08％，SiO27.05％，Al2O31.72% and CaO2.05%. In this example, the raw materials were recycled, and the components and contents thereof do not limit the embodiment.
Example 1:
the process flow refers to the figure 1, and comprises the following steps:
1) ash removal: removing dust particles attached to the surface of the catalyst by adopting a high-pressure air ash removal mode for the received waste catalyst;
2) pretreatment: pre-crushing the ash-removed waste catalyst to form particles smaller than 10 mm;
3) physical separation: adding the waste catalyst with the diameter less than 10mm into a jet mill, and grading by a grader to obtain a high-silicon material and a low-silicon material respectively. Wherein, the mass content of silicon dioxide in the high-silicon material is more than 20 percent, and the high-silicon material can be directly reused for preparing a fresh denitration catalyst or can be used for obtaining a silicic acid product after alkaline leaching and pH adjustment. The low-silicon material contains less than 0.5 percent of silicon dioxide, less than 0.4 percent of aluminum oxide, 0.1 percent of calcium oxide and powder d90Less than 25 microns.
4) And (3) carrying out alkaline leaching process treatment on the separated low-silicon material, wherein the mass of sodium hydroxide is 2 times that of the low-silicon material, the concentration of the ore pulp is 5% after water is added, the reaction temperature is 130 ℃, and the reaction time is 1 hour.
5) And after the alkaline leaching is finished, carrying out solid-liquid separation on the alkaline leaching solution, and fully washing and drying the separated solid phase to obtain the titanium dioxide product.
6) Adding hydrogen peroxide into the filtrate in the last step, oxidizing for 1 hour, adding hydrochloric acid, reacting for 1 hour at 80 ℃, and carrying out solid-liquid separation after the reaction is finished to obtain the tungstic acid product.
7) And adding calcium chloride into the filtrate obtained in the last step, fully reacting for 1.5 hours, and performing solid-liquid separation to obtain a solid phase of calcium vanadate.
Example 2:
the method for recycling the waste denitration catalyst comprises the following steps:
1) ash removal: removing dust particles attached to the surface of the catalyst by adopting a high-pressure air ash removal mode for the received waste catalyst;
2) pretreatment: pre-crushing the ash-removed waste catalyst to form particles smaller than 10 mm;
3) physical separation: adding the waste catalyst with the diameter less than 10mm into a jet mill, and grading by a grader to obtain a high-silicon material and a low-silicon material respectively. Wherein, the content of silicon dioxide in the low-silicon material is less than 0.5 percent, the content of aluminum oxide is less than 0.1 percent, the content of calcium oxide is 0.5 percent, and the powder d90Less than 25 microns.
4) And (3) carrying out alkaline leaching process treatment on the separated low-silicon material, wherein the mass of potassium hydroxide is 1.2 times that of the low-silicon material, the concentration of the ore pulp is 10% after water is added, the reaction temperature is 90 ℃, and the reaction time is 2 hours.
5) And after the alkaline leaching is finished, carrying out solid-liquid separation on the alkaline leaching solution, and fully washing and drying the separated solid phase to obtain the titanium dioxide product.
6) Adding hydrogen peroxide into the filtrate in the last step, oxidizing for 1 hour, adding hydrochloric acid, reacting for 1 hour at 80 ℃, and carrying out solid-liquid separation after the reaction is finished to obtain the tungstic acid product.
7) And adding calcium chloride into the filtrate obtained in the last step, fully reacting for 1.0 hour, and performing solid-liquid separation to obtain a solid phase of calcium vanadate.
Example 3:
the method for recycling the waste denitration catalyst comprises the following steps:
1) ash removal: removing dust particles attached to the surface of the catalyst by adopting a high-pressure air ash removal mode for the received waste catalyst;
2) pretreatment: pre-crushing the ash-removed waste catalyst to form particles smaller than 10 mm;
3) physical separation: adding the waste catalyst with the diameter less than 10mm into a jet mill, and grading by a grader to obtain a high-silicon material and a low-silicon material respectively. Wherein, the content of silicon dioxide in the low-silicon material is less than 0.8 percent, the content of aluminum oxide is less than 0.3 percent, the content of calcium oxide is 0.2 percent, and the powder d90Less than 10 microns.
4) And (3) carrying out alkaline leaching process treatment on the separated low-silicon material, wherein the mass of sodium hydroxide is 0.5 time of that of the low-silicon material, the concentration of the ore pulp is 25% after water is added, the reaction temperature is 60 ℃, and the reaction time is 4 hours.
5) And after the alkaline leaching is finished, carrying out solid-liquid separation on the alkaline leaching solution, and fully washing and drying the separated solid phase to obtain the titanium dioxide product.
6) Adding hydrogen peroxide into the filtrate in the last step, oxidizing for 2 hours, adding hydrochloric acid, reacting for 1 hour at 60 ℃, and carrying out solid-liquid separation after the reaction is finished to obtain the tungstic acid product.
7) And adding calcium chloride into the filtrate obtained in the last step, fully reacting for 2.0 hours, and performing solid-liquid separation to obtain a solid phase of calcium vanadate.
Example 4
A recovery device for waste denitration catalyst comprises a waste catalyst storage bin, an ash removal device, a pretreatment device, a physical separation device, a high-silicon material storage bin, a low-silicon material storage bin, an alkaline leaching device, a first solid-liquid separation device, a tungsten precipitation device, a second solid-liquid separation device, a vanadium precipitation device and a third solid-liquid separation device;
the waste catalyst storage bin is connected with the ash removal device, the ash removal device is connected with the pretreatment device, the pretreatment device is connected with the physical separation device, the physical separation device separates to obtain a high-silicon material and conveys the high-silicon material to the high-silicon material storage bin, and the physical separation device separates to obtain a low-silicon material and conveys the low-silicon material to the low-silicon material storage bin;
the low-silicon material storage bin is connected with the alkaline leaching device, the alkaline leaching device is connected with the first solid-liquid separation device, and filtrate 1 and filter residue 1 are obtained through solid-liquid separation; the filtrate 1 is conveyed to the tungsten precipitation device, is subjected to oxidation, acid addition and tungsten precipitation reaction, is conveyed to the second solid-liquid separation device, and is subjected to solid-liquid separation to obtain a filtrate 2 and a filter residue 2; and conveying the filtrate 2 to the vanadium precipitation device, conveying to the third solid-liquid separation device after vanadium precipitation by calcium salt, and performing solid-liquid separation to obtain filtrate 3 and filter residue 3.
Preferably, the pre-treatment device is a coarse crushing device, and the physical separation device comprises a jet mill and a classifier.
The use method of the device is as follows:
conveying the waste denitration catalyst in the waste catalyst storage bin to an ash removal device for compressed air or high-pressure water cleaning of catalyst attached dust, and then conveying the waste denitration catalyst to a pretreatment device for coarse crushing, wherein the particle size of the particles after coarse crushing is less than 5 mm. Then the coarsely crushed particles are conveyed to a physical separation device for separation, the catalyst is scattered by utilizing the air flow crushing principle, the coarsely crushed particles are gradually crushed into fine particles under the repeated high-speed impact and collision, and the glass fiber still keeps larger particle size due to the characteristic of fibrous and higher toughness; the powder formed after the catalyst is scattered enters a grading chamber along with the airflow, the grading rotor rotates at a high speed, under the combined action of centrifugal force and centripetal force, coarse particles return to an airflow crushing chamber, fine particles enter a catcher along with the airflow and are collected to respectively obtain a low-silicon material and a high-silicon material, the low-silicon material is positioned in the catcher, and the high-silicon material is positioned in the airflow crushing chamber.
Conveying the low-silicon material to a low-silicon material storage bin, then conveying the low-silicon material storage bin to an alkaline leaching device, adding solid alkali to carry out alkaline leaching, conveying the low-silicon material to a first solid-liquid separation device after the reaction is finished, and carrying out solid-liquid separation to obtain filtrate 1 and filter residue 1; the filtrate 1 is conveyed to the tungsten precipitation device, is conveyed to the second solid-liquid separation device after being oxidized and subjected to tungsten precipitation reaction by adding acid, and is subjected to solid-liquid separation to obtain a filtrate 2 and a filter residue 2; and conveying the filtrate 2 to the vanadium precipitation device, precipitating vanadium by using a calcium salt, conveying to the third solid-liquid separation device, and performing solid-liquid separation to obtain a filtrate 3 and a filter residue 3.
And conveying the high-silicon material to the high-silicon material storage bin, wherein the high-silicon material can be reused for preparing a fresh denitration catalyst, or the high-silicon material is subjected to alkaline leaching and pH adjustment to obtain silicic acid.
Example 5:
the method for recycling the waste denitration catalyst comprises the following steps:
1) ash removal: removing dust particles attached to the surface of the catalyst by adopting a high-pressure water cleaning mode for the received waste catalyst;
2) pretreatment: pre-crushing the ash-removed waste catalyst to form particles smaller than 1 mm;
3) physical separation: adding the waste catalyst with the diameter less than 1mm into a jet mill, and grading by a grader to obtain a high-silicon material and a low-silicon material respectively. Wherein, the mass content of silicon dioxide in the high-silicon material is more than 30 percent, and the high-silicon material can be directly reused for preparing a fresh denitration catalyst or can be used for preparing a silicic acid product after alkaline leaching and pH adjustment. The low-silicon material contains less than 0.1 percent of silicon dioxide, less than 0.4 percent of aluminum oxide, less than 0.1 percent of calcium oxide and powder d90Less than 25 microns.
4) And (3) carrying out alkaline leaching process treatment on the separated low-silicon material, wherein the mass of sodium hydroxide is 1 time of that of the low-silicon material, the concentration of the ore pulp is 18 percent after water is added, the reaction temperature is 120 ℃, and the reaction time is 1 hour.
5) And after the alkaline leaching is finished, carrying out solid-liquid separation on the alkaline leaching solution, and fully washing and drying the separated solid phase to obtain the titanium dioxide product.
6) Adding hydrogen peroxide into the filtrate in the last step, oxidizing for 1 hour, adding hydrochloric acid, reacting for 1 hour at 80 ℃, and carrying out solid-liquid separation after the reaction is finished to obtain the tungstic acid product.
7) And adding calcium chloride into the filtrate obtained in the last step, fully reacting for 1.5 hours, and performing solid-liquid separation to obtain a solid phase of calcium vanadate.
Example 6:
the method for recycling the waste denitration catalyst comprises the following steps:
1) ash removal: removing dust particles attached to the surface of the catalyst by adopting a high-pressure air ash removal mode for the received waste catalyst;
2) pretreatment: pre-crushing the ash-removed waste catalyst to form particles smaller than 6 mm;
3) physical separation: adding the waste catalyst with the diameter less than 6mm into a jet mill, and grading by a grader to obtain a high-silicon material and a low-silicon material respectively. Wherein, the content of silicon dioxide in the low-silicon material is less than 0.5 percent, the content of aluminum oxide is less than 0.1 percent, the content of calcium oxide is less than 0.5 percent, and the powder d90Less than 25 microns.
4) And (3) carrying out alkaline leaching treatment on the separated low-silicon material, wherein the mass of potassium hydroxide is 1/2 of the low-silicon material, the concentration of the ore pulp is 15% after water is added, the reaction temperature is 70 ℃, and the reaction time is 2 hours.
5) And after the alkaline leaching is finished, carrying out solid-liquid separation on the alkaline leaching solution, and fully washing and drying the separated solid phase to obtain the titanium dioxide product.
6) Adding hydrogen peroxide into the filtrate in the last step, oxidizing for 1 hour, adding hydrochloric acid, reacting for 1 hour at 80 ℃, and carrying out solid-liquid separation after the reaction is finished to obtain the tungstic acid product.
7) And adding calcium chloride into the filtrate obtained in the last step, fully reacting for 1.0 hour, and performing solid-liquid separation to obtain a solid phase of calcium vanadate.
Comparative example 1
The method for recycling the waste denitration catalyst comprises the following steps:
1) ash removal: removing dust particles attached to the surface of the catalyst by adopting a high-pressure air ash removal mode for the received waste catalyst;
2) pretreatment: pre-crushing the ash-removed waste catalyst to form particles smaller than 10 mm;
3) and (3) carrying out alkaline leaching treatment on the waste catalyst with the particle size less than 10mm, wherein the mass of potassium hydroxide is 2 times that of the low-silicon material, the concentration of the ore pulp is 5% after water is added, the reaction temperature is 130 ℃, the reaction time is 1 hour, and valuable elements cannot be separated.
Further analysis shows that silicon, aluminum and calcium in the waste catalyst with the diameter less than 10mm account for 10.82 wt% of the waste catalyst and far exceed 2.85 wt% of target elements vanadium and tungsten, on one hand, impurities can reduce the reaction efficiency of vanadium, tungsten and alkali liquor, on the other hand, impurities silicon reacts with the alkali liquor to form silicate, enters the solution, the viscosity of the solution is greatly improved, normal leaching operation is influenced, and the leaching effect is further reduced. In addition, in the subsequent tungsten precipitation stage by adding acid, silicon and tungsten are precipitated by silicic acid and tungstic acid respectively, and the purification of tungsten cannot be realized.
The preferred embodiments of the present invention have been described in detail, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.
It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. The invention is not described in detail in order to avoid unnecessary repetition.
In addition, any combination of the various embodiments of the present invention can be made, and the same should be considered as the disclosure of the present invention as long as the idea of the present invention is not violated.

Claims (13)

1. A method for recovering a waste denitration catalyst is characterized by comprising the following steps:
step 1) carrying out ash removal and pretreatment on a waste denitration catalyst;
step 2) treating the pretreated catalyst by adopting a physical separation process to obtain a low-silicon material and a high-silicon material;
step 3) carrying out alkaline leaching on the separated low-silicon material, and filtering to obtain a filtrate 1 and a filter residue 1;
step 4) washing, drying and calcining the filter residue 1 obtained in the step 3) to obtain titanium dioxide;
step 5) separating and purifying tungsten and vanadium in the filtrate 1 obtained in the step 3) to respectively obtain tungstic acid and vanadate;
in the step 2), the catalyst is broken up by using the jet milling principle, large particles are gradually milled into fine particles under repeated high-speed impact and collision, and the glass fiber still keeps larger particle size due to the characteristics of special fibrous shape and higher toughness; the powder formed after the catalyst is scattered enters a grading chamber along with the airflow, the grading rotor rotates at a high speed, under the combined action of centrifugal force and centripetal force, coarse particles return to an airflow crushing chamber, fine particles enter a catcher along with the airflow and are collected to respectively obtain a low-silicon material and a high-silicon material, the low-silicon material is positioned in the catcher, and the high-silicon material is positioned in the airflow crushing chamber.
2. The method of claim 1, wherein the method comprises the steps of: the ash removal mode in the step 1) is to clean the dust attached to the catalyst by compressed air or high-pressure water, the pretreatment is coarse crushing, and the particle size of the coarsely crushed particles is less than 10 mm.
3. The method of claim 1, wherein the method comprises the steps of: in the step 2), the physical separation process comprises the following steps: the catalyst is broken up by utilizing the jet milling principle and then separated by a grading device to obtain a low-silicon material and a high-silicon material.
4. The method of recovering a spent denitration catalyst according to any one of claims 1 to 3, characterized in that: in the step 2), the mass content of silicon dioxide in the high-silicon material is more than 20%, the mass content of silicon dioxide in the low-silicon material is less than 1.0%, and the 45-micron sieve passing rate of the low-silicon material is more than 95%.
5. The method of claim 4, wherein the method comprises the steps of: the high-silicon material is recycled for preparing a fresh denitration catalyst, or is subjected to alkaline leaching and pH adjustment to obtain silicic acid.
6. The method of claim 4, wherein the method comprises the steps of: in the step 3), the alkaline leaching is performed by adopting solid alkali and the low-silicon material in a mass ratio of 0.5-2.0, the mass concentration of ore pulp is 5-25%, the temperature of the alkaline leaching is 60-130 ℃, and the reaction time is 1-4 hours.
7. The method of claim 6, wherein the method comprises: the solid alkali is one or the combination of two of sodium hydroxide and potassium hydroxide in any proportion.
8. The method of recovering a spent denitration catalyst according to any one of claims 1 to 3, characterized in that: the method for separating and purifying tungsten and vanadium in the step 5) comprises the following steps: adding an oxidant into the filtrate 1, carrying out an oxidation reaction, adding an inorganic acid, carrying out solid-liquid separation to obtain a filter residue 2 and a filtrate 2, adjusting the pH of the filtrate 2 to 8-10, adding a calcium salt into the filtrate 2, and carrying out solid-liquid separation to obtain a filter residue 3 and a filtrate 3; and the filter residue 2 contains tungsten element, and the filter residue 3 contains vanadium element, so that the separation of tungsten and vanadium is realized.
9. The method of recovering a spent denitration catalyst according to claim 8, characterized in that: the inorganic acid is one or any combination of two of hydrochloric acid or sulfuric acid.
10. The method of claim 9, wherein the method comprises: the filter residue 2 is tungstic acid, the filter residue 3 is vanadate, and the calcium salt is calcium chloride.
11. An apparatus for recovering a spent denitration catalyst, which is used for recovering a spent denitration catalyst by the method for recovering a spent denitration catalyst according to any one of claims 1 to 10, characterized in that: the device comprises a waste catalyst storage bin, an ash cleaning device, a pretreatment device, a physical separation device, a high-silicon material storage bin, a low-silicon material storage bin, an alkaline leaching device, a first solid-liquid separation device, a tungsten precipitation device, a second solid-liquid separation device, a vanadium precipitation device and a third solid-liquid separation device;
the ash cleaning device is connected with the pretreatment device, the pretreatment device is connected with the physical separation device, the physical separation device separates high-silicon materials to be conveyed to the high-silicon material storage bin, and the physical separation device separates low-silicon materials to be conveyed to the low-silicon material storage bin;
the low-silicon material storage bin is connected with the alkaline leaching device, the alkaline leaching device is connected with the first solid-liquid separation device, and filtrate 1 and filter residue 1 are obtained through solid-liquid separation; the filtrate 1 is conveyed to the tungsten precipitation device, is conveyed to the second solid-liquid separation device after being oxidized and subjected to tungsten precipitation reaction by adding acid, and is subjected to solid-liquid separation to obtain a filtrate 2 and a filter residue 2; and conveying the filtrate 2 to the vanadium precipitation device, conveying to the third solid-liquid separation device after vanadium precipitation by calcium salt, and performing solid-liquid separation to obtain filtrate 3 and filter residue 3.
12. The apparatus for recovering a spent denitration catalyst according to claim 11, characterized in that: the pretreatment device is a coarse crushing device.
13. The apparatus for recovering a spent denitration catalyst according to claim 11, characterized in that: the physical separation device comprises a jet mill and a classifier.
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Publication number Priority date Publication date Assignee Title
CN111689521B (en) * 2020-06-20 2024-03-08 太原理工大学 Recovery treatment method of waste SCR denitration catalyst
CN111876604A (en) * 2020-08-03 2020-11-03 江苏肯创催化剂再生技术有限公司 Process method for treating and utilizing sulfuric acid catalyst prepared from waste vanadium-silicon system

Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1958446A (en) * 2006-11-17 2007-05-09 四川大学 Method for preparing high purity super fine silicon miropowder by using powder of natural quartz
CN102145898A (en) * 2011-05-05 2011-08-10 张冬玲 Production method of silicon dioxide ultrafine powder
CN102936039A (en) * 2012-11-15 2013-02-20 攀枝花市晟天钛业有限公司 Recovery process of honeycomb type selective catalytic reduction (SCR) waste catalyst containing tungsten, vanadium and titanium
CN103526031A (en) * 2013-10-09 2014-01-22 北京科技大学 Recovery method for SCR waste flue gas denitration catalyst
CN103553625A (en) * 2013-11-16 2014-02-05 连云港龙塔研磨材料有限公司 Method for preparing silicon carbide micro powder for fine silicon carbide ceramics
CN104726713A (en) * 2015-02-16 2015-06-24 浙江大学 Process for comprehensive recovery of metal-containing oxides in disabled SCR (selective catalytic reduction) denitration catalyst
CN104805298A (en) * 2015-05-22 2015-07-29 北京赛科康仑环保科技有限公司 Method for recovering waste SCR (Selective Catalytic Reduction) denitration catalyst
CN104909369A (en) * 2015-05-28 2015-09-16 济南骄泰信息技术有限公司 Ultra-fine metal silicon powder production method
CN105536817A (en) * 2015-09-11 2016-05-04 福建紫荆环境工程技术有限公司 Waste SCR denitration catalyst comprehensive recovery and utilization method and system
CN106944222A (en) * 2017-02-10 2017-07-14 广州中卓智能装备有限公司 A kind of jet mill grinding technique of powder
CN107196007A (en) * 2017-05-27 2017-09-22 南京博驰新能源股份有限公司 A kind of lithium battery recycling method
CN107557599A (en) * 2017-07-20 2018-01-09 北京世纪地和控股有限公司 Tungsten, the method for vanadium are reclaimed in discarded SCR denitration
CN110117722A (en) * 2019-06-06 2019-08-13 中国华能集团清洁能源技术研究院有限公司 Vanadium titanium tungsten system denitrating catalyst resource utilization and water circulation utilization system and method
CN110578058A (en) * 2019-09-28 2019-12-17 中国电建集团装备研究院有限公司 method for recovering titanium, tungsten, vanadium and silicon in waste catalyst for coal-fired flue gas denitration

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101452179B1 (en) * 2014-03-11 2014-10-24 한국지질자원연구원 Recovery method of vanadium and tungsten from leaching solution of spent catalyst of denitrification

Patent Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1958446A (en) * 2006-11-17 2007-05-09 四川大学 Method for preparing high purity super fine silicon miropowder by using powder of natural quartz
CN102145898A (en) * 2011-05-05 2011-08-10 张冬玲 Production method of silicon dioxide ultrafine powder
CN102936039A (en) * 2012-11-15 2013-02-20 攀枝花市晟天钛业有限公司 Recovery process of honeycomb type selective catalytic reduction (SCR) waste catalyst containing tungsten, vanadium and titanium
CN103526031A (en) * 2013-10-09 2014-01-22 北京科技大学 Recovery method for SCR waste flue gas denitration catalyst
CN103553625A (en) * 2013-11-16 2014-02-05 连云港龙塔研磨材料有限公司 Method for preparing silicon carbide micro powder for fine silicon carbide ceramics
CN104726713A (en) * 2015-02-16 2015-06-24 浙江大学 Process for comprehensive recovery of metal-containing oxides in disabled SCR (selective catalytic reduction) denitration catalyst
CN104805298A (en) * 2015-05-22 2015-07-29 北京赛科康仑环保科技有限公司 Method for recovering waste SCR (Selective Catalytic Reduction) denitration catalyst
CN104909369A (en) * 2015-05-28 2015-09-16 济南骄泰信息技术有限公司 Ultra-fine metal silicon powder production method
CN105536817A (en) * 2015-09-11 2016-05-04 福建紫荆环境工程技术有限公司 Waste SCR denitration catalyst comprehensive recovery and utilization method and system
CN106944222A (en) * 2017-02-10 2017-07-14 广州中卓智能装备有限公司 A kind of jet mill grinding technique of powder
CN107196007A (en) * 2017-05-27 2017-09-22 南京博驰新能源股份有限公司 A kind of lithium battery recycling method
CN107557599A (en) * 2017-07-20 2018-01-09 北京世纪地和控股有限公司 Tungsten, the method for vanadium are reclaimed in discarded SCR denitration
CN110117722A (en) * 2019-06-06 2019-08-13 中国华能集团清洁能源技术研究院有限公司 Vanadium titanium tungsten system denitrating catalyst resource utilization and water circulation utilization system and method
CN110578058A (en) * 2019-09-28 2019-12-17 中国电建集团装备研究院有限公司 method for recovering titanium, tungsten, vanadium and silicon in waste catalyst for coal-fired flue gas denitration

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