阅读说明：本技术 具有除尘和催化净化VOCs功能的金属纤维滤料及其制备方法 (Metal fiber filter material with dust removal and VOCs (volatile organic compounds) catalytic purification functions and preparation method thereof ) 是由 田振玉 樊振国 于丹 于 2021-08-06 设计创作，主要内容包括：本发明公开了一种具有除尘和催化净化VOCs功能的金属纤维滤料的制备方法,该制备方法包括：提供一金属纤维毡衬底；配置催化剂前驱体溶液,催化剂前驱体溶液包括前驱体和燃烧性溶剂；采用雾化送样将催化剂前驱体溶液送入燃烧器,雾化后的催化剂前驱体溶液与氧化剂在燃烧器中混合；在燃烧器中加入燃料和浴气,使雾化后的催化剂前驱体溶液、氧化剂、燃料和浴气共同燃烧；雾化后的催化剂前驱体溶液经热解后,形成催化剂核；催化剂核聚集、长大,并沉积到金属纤维毡衬底上,形成具有除尘和催化净化VOCs功能的金属纤维滤料。本发明还提供一种利用上述方法得到的具有除尘和催化净化VOCs功能的金属纤维滤料及其在净化处理含有粉尘和VOCs的混合废气中的应用。(The invention discloses a preparation method of a metal fiber filter material with the functions of dedusting and catalytic purification of VOCs, which comprises the following steps: providing a metal fiber felt substrate; preparing a catalyst precursor solution, wherein the catalyst precursor solution comprises a precursor and a combustible solvent; feeding the catalyst precursor solution into a combustor by adopting an atomization sample feeding method, and mixing the atomized catalyst precursor solution and an oxidant in the combustor; adding fuel and bath gas into a combustor to enable the atomized catalyst precursor solution, oxidant, fuel and bath gas to be combusted together; pyrolyzing the atomized catalyst precursor solution to form catalyst nuclei; the catalyst nuclei gather and grow up and are deposited on the metal fiber felt substrate to form the metal fiber filter material with the functions of dedusting and catalyzing and purifying VOCs. The invention also provides a metal fiber filter material with the functions of dedusting and catalytic purification of VOCs obtained by the method and application thereof in purification treatment of mixed waste gas containing dust and VOCs.)

1. A preparation method of a metal fiber filter material with the functions of removing dust and catalytically purifying VOCs is characterized by comprising the following steps:

providing a metal fiber felt substrate;

depositing a catalyst on the metal fiber felt substrate by adopting a flame spraying catalyst loading method to form a metal fiber filter material with the functions of dedusting and catalytic purification of VOCs;

wherein the depositing a catalyst on the metal fiber felt substrate using a flame spray catalyst loading method comprises:

preparing a catalyst precursor solution, wherein the catalyst precursor solution comprises a precursor and a combustible solvent;

feeding the catalyst precursor solution into a combustor by adopting an atomization sample feeding method, and mixing the atomized catalyst precursor solution and an oxidant in the combustor;

adding fuel and bath gas into the burner, and co-combusting the atomized catalyst precursor solution, the oxidant, the fuel and the bath gas;

pyrolyzing the atomized catalyst precursor solution to form catalyst nuclei;

the catalyst nuclei aggregate, grow, and deposit onto the metal fiber felt substrate.

2. The method of claim 1, wherein the burner is one or more;

the burner comprises a plurality of flame distributors, and the flame distributors are uniformly distributed in the burner.

3. The method of claim 1, wherein the metal fiber felt substrate comprises a stainless steel fiber felt, an iron chromium aluminum fiber felt or a hastelloy fiber felt;

said providing a metal fiber mat substrate comprises: and performing composite assembly and multi-strand drawing on the metal wire by using a cluster drawing process to manufacture micron-sized fiber wires, and performing felting, vacuum sintering and welding assembly on the fiber wires to obtain the metal fiber felt substrate.

4. The method of claim 1, wherein the catalyst comprises at least one of: iridium oxide, palladium oxide, ruthenium oxide, rhodium oxide, iron oxide, cerium oxide, aluminum oxide, chromium oxide, barium oxide, zinc oxide, lanthanum cobalt oxide, lanthanum manganese oxide, perovskite.

5. The method of claim 1, wherein the atomized feed is a pulsed atomized feed having a radio frequency and a pulse width that control the growth rate of the catalyst nuclei, wherein the radio frequency is less than 100Hz and the pulse width is on the order of milliseconds.

6. The method of claim 1, wherein the oxidizing agent comprises one of: air, oxygen, a mixture of air and oxygen;

the fuel comprises a gaseous fuel or a liquid fuel;

the bath gas comprises nitrogen or an inert gas.

7. The method of claim 1, wherein the amount of the oxidant entering the burner is regulated with a first flow controller; regulating an amount of the fuel entering the burner with a second flow controller; and regulating the amount of the bath gas entering the burner by using a third flow controller.

8. The method of claim 1, wherein the precursor comprises at least one of: iridium acetylacetonate, palladium acetate, ruthenium acetate, rhodium acetylacetonate, iron acetylacetonate, cerium acetylacetonate, aluminum acetylacetonate, chromium acetylacetonate, barium acetylacetonate, zinc acetylacetonate hydrate, lanthanum acetylacetonate hydrate, cobalt acetylacetonate, manganese acetylacetonate, and billows hydrate;

the burnable aid comprises ethanol;

the concentration of the precursor is in the order of millimoles per liter.

9. A metal fiber filter material with the functions of removing dust and catalytically purifying VOCs, which is obtained by the preparation method of any one of claims 1-8.

10. Use of a metal fiber filter material according to claim 9 for the purification treatment of mixed exhaust gases containing dust and VOCs.

Technical Field

The invention relates to the field of flue gas purification, in particular to a metal fiber filter material with functions of dedusting and catalytic purification of VOCs (volatile organic compounds) and a preparation method thereof.

Background

Volatile Organic Compounds (VOCs) are Organic Compounds having a saturated vapor pressure at ambient temperature of greater than about 70Pa and a boiling point at ambient pressure of less than 260 ℃.

In industrial production and fuel combustion processes, dust and various volatile organic compounds are inevitably generated, and particularly in high-temperature heating and organic solvent cooling processes, high-temperature dust and organic compounds are generated in a large amount and need to be purified. In order to reduce cost and realize low-carbon and high-efficiency short-flow treatment effects, the metal fiber high-temperature filter material is more and more emphasized.

At present, the metal fiber filter material mainly plays a role in filtering dust, but dust and organic matters are mostly generated simultaneously in the industrial production process, and are simultaneously mixed and discharged to the waste gas purification treatment equipment. Therefore, the dust removal filter material made of metal fiber, natural fiber filter material, chemical fiber or glass fiber with single function is often blocked or aged due to the cooling and gathering of organic components, and loses the purification performance; and simultaneously, the discharged organic waste gas needs to be provided with other VOCs treatment equipment for recovery or purification treatment, so that the investment cost of enterprises is increased.

In the related art, chinese patent document No. CN104226020B proposes a method for preparing a filter material for simultaneously removing dust and removing harmful gases by catalysis, wherein the filter material prepared by the method comprises a dust facing layer, a buffer layer, a catalytic filter layer and a support layer which are sequentially laminated; wherein the catalytic filter layer is prepared by electrostatic spinning to obtain SiO₂-TiO₂After the nanofibers, catalytically active components are loaded on the nanofibers by a solvothermal synthesis method. But because the preparation method adopts SiO₂-TiO₂The composite nanofiber has the advantages of complex manufacturing process, high cost, unsuitability for large-scale production and manufacturing, long manufacturing process, low efficiency and high price, and needs auxiliary matching of structures such as a windward layer, a buffer layer, a supporting layer and the like. And in 2017, 10, 27 days, the carcinogen list published by the international cancer research institution of the world health organization is preliminarily collated and referred, fibers with special purposes, such as E glass and '475' glass fibers, are in the 2B class carcinogen list, continuous glass fibers are in the 3 class carcinogen list, and glass fiber filter materials gradually enter a phase of elimination.

Based on the above circumstances, it is of great significance to develop a novel metal fiber filter material with dust removal and VOCs catalytic purification functions.

Disclosure of Invention

In view of the above, the present invention provides a metal fiber filter material with functions of removing dust and catalytically purifying VOCs and a preparation method thereof, in order to simultaneously purify and treat mixed waste gas containing dust and VOCs.

The invention provides a preparation method of a metal fiber filter material with the functions of dedusting and catalytic purification of VOCs, which comprises the following steps: providing a metal fiber felt substrate; depositing a catalyst on a metal fiber felt substrate by adopting a flame spraying catalyst loading method to form a metal fiber filter material with the functions of dedusting and catalytic purification of VOCs; wherein depositing a catalyst on a metal fiber felt substrate using a flame spray catalyst loading method comprises: preparing a catalyst precursor solution, wherein the catalyst precursor solution comprises a precursor and a combustible solvent; feeding the catalyst precursor solution into a combustor by adopting an atomization sample feeding method, and mixing the atomized catalyst precursor solution and an oxidant in the combustor; adding fuel and bath gas into a combustor to enable the atomized catalyst precursor solution, oxidant, fuel and bath gas to be combusted together; pyrolyzing the atomized catalyst precursor solution to form catalyst nuclei; the catalyst nuclei aggregate, grow, and deposit onto the metal fiber felt substrate.

In some embodiments, the burners are one or more; the burner includes a plurality of flame distributors, and the plurality of flame distributors are evenly distributed in the burner.

In some embodiments, the metal fiber mat substrate comprises a stainless steel fiber mat, an iron chromium aluminum fiber mat, or a hastelloy fiber mat.

In some embodiments, providing a metal fiber mat substrate comprises: and (3) compositely assembling the metal wire by using a cluster drawing process, drawing multiple strands for multiple times to manufacture micron-sized fiber wires, and paving, vacuum sintering, welding and assembling the micron-sized fiber wires to obtain the metal fiber felt substrate.

In some embodiments, the catalyst comprises at least one of: iridium oxide, palladium oxide, ruthenium oxide, rhodium oxide, iron oxide, cerium oxide, aluminum oxide, chromium oxide, barium oxide, zinc oxide, lanthanum cobalt oxide, lanthanum manganese oxide, perovskite.

In some embodiments, the atomized feed is a pulsed atomized feed, the rf frequency and pulse width of the pulsed atomized feed controlling the growth rate of the catalyst nuclei, wherein the rf frequency is less than 100Hz and the pulse width is on the order of milliseconds.

In some embodiments, the oxidizing agent comprises one of: air, oxygen, and a mixture of air and oxygen.

In some embodiments, the fuel comprises a gaseous fuel or a liquid fuel.

In some embodiments, the bath gas comprises nitrogen or an inert gas.

In some embodiments, the amount of oxidant entering the combustor is regulated with a first flow controller; regulating the amount of fuel entering the burner with a second flow controller; and regulating the amount of the bath gas entering the combustor by using a third flow controller.

In some embodiments, the precursor comprises at least one of: iridium acetylacetonate, palladium acetate, ruthenium acetate, rhodium acetylacetonate, iron acetylacetonate, cerium acetylacetonate, aluminum acetylacetonate, chromium acetylacetonate, barium acetylacetonate, zinc acetylacetonate hydrate, lanthanum acetylacetonate hydrate, cobalt acetylacetonate, manganese acetylacetonate, and billows hydrate.

In some embodiments, the flammability aid includes ethanol.

In some embodiments, the concentration of the precursor is on the order of millimoles per liter.

The invention also provides a metal fiber filter material with the functions of dedusting and catalytic purification of VOCs, which is obtained by the preparation method.

The invention also provides application of the metal fiber filter material in purifying mixed waste gas containing dust and VOCs.

The metal fiber filter material with the functions of dedusting and catalytic purification of VOCs and the preparation method thereof provided by the invention have the following beneficial effects:

(1) can purify dust and VOCs gas simultaneously, be applicable to the mixed waste gas that purification treatment contains VOCs gas and dust.

(2) The preparation method has the advantages of simple process, safety, high efficiency and no secondary pollution.

(3) The structure of the catalyst can be regulated and controlled by controlling the amount of the atomized catalyst precursor solution, the oxidant, the fuel and the bath gas, and the preparation process is stable and reliable.

Drawings

FIG. 1 is a flow chart of a process for preparing a metal fiber filter material according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a process for preparing a metal fiber filter material according to an embodiment of the present invention;

FIG. 3 is a flow chart of a process for preparing a metal fiber mat substrate according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a metal fiber filter material provided in an embodiment of the present invention.

[ description of reference ]

1-a metal fiber felt substrate; 2-a burner; 3-catalyst precursor solution inlet; 4-a pulse nozzle; 5-oxidant inlet; 6-fuel and bath gas inlet; 7-atomized catalyst precursor solution; 8-a flame distributor; 9-catalyst particle layer

Detailed Description

In order that the objects, technical solutions and advantages of the present invention will become more apparent, the present invention will be further described in detail with reference to the accompanying drawings in conjunction with the following specific embodiments.

The invention provides a metal fiber filter material with the functions of dedusting and catalytic purification of VOCs and a preparation method thereof. And depositing a catalyst on the metal fiber felt substrate by adopting a flame spraying catalyst loading method to form the metal fiber filter material with the functions of dedusting and catalyzing and purifying VOCs. The flame spraying catalyst loading method is that catalyst precursor solution is atomized and injected into flame to react to form prefabricated material core, and the prefabricated material core is sprayed onto the metal fiber felt substrate to synthesize film or nanometer particle with high stability and high activity.

Fig. 1 is a flow chart of a preparation process of a metal fiber filter material according to an embodiment of the present invention. Fig. 2 is a schematic view of a preparation process of a metal fiber filter material provided in an embodiment of the present invention. As shown in fig. 1 and 2, the preparation method includes operations S101 to S107.

In operation S101, a metal fiber mat substrate 1 is provided, including selection and pretreatment of the metal fiber mat substrate 1.

According to an embodiment of the present invention, the metal fiber felt substrate 1 may be a stainless steel fiber felt, an iron chromium aluminum fiber felt, or a hastelloy fiber felt.

According to the embodiment of the invention, the metal fiber filter material 1 has the function of filtering dust and can intercept particles about 0.5 μm. The metal fiber filter material 1 has the characteristics of high porosity (up to 90%) and good air permeability.

According to the embodiment of the invention, a suitable metal fiber felt 1 is selected as the substrate according to the requirements of the actual process. According to different temperatures of waste gas to be treated, the metal fiber felt substrate 1 meeting different temperature conditions is selected. Wherein the stainless steel metal fiber felt can be used for a long time below 450 ℃, and the iron chromium aluminum fiber felt can be used for a long time below 600 ℃. Fig. 3 is a flow chart of a process for preparing the metal fiber mat substrate 1 according to the embodiment of the present invention.

Referring to fig. 3, providing a metal fiber mat substrate 1 includes: and (3) compositely assembling the metal wire by using a cluster drawing process, drawing multiple strands for multiple times to manufacture micron-sized fiber wires, and paving, vacuum sintering, welding and assembling the micron-sized fiber wires to obtain the metal fiber felt. The technology can be used for producing the metal fiber felt on a large scale, and has high efficiency, low price and no secondary pollution.

According to an embodiment of the invention, the wire may be of the class 316L, 310S or FeCrAl.

According to embodiments of the present invention, different classes and sizes of wires may be selected depending on the density of the supported catalyst.

The metal fiber felt substrate has the characteristic of easy ash removal, is easy to recycle after use, and does not cause secondary pollution to the environment.

In operation S102, a catalyst precursor solution is prepared, the catalyst precursor solution including a precursor and a flammable solvent.

According to an embodiment of the invention, the precursor may comprise at least one of: iridium acetylacetonate, palladium acetate, ruthenium acetate.

According to the embodiment of the invention, the concentration of the precursor is configured according to the characteristics and temperature requirements of the catalyst; wherein the concentration of the precursor is in the order of millimoles per liter.

According to the embodiment of the invention, the combustible auxiliary agent can be ethanol or other alcohol solvents.

According to the embodiment of the invention, the selection of the catalyst is related to the preparation requirement of the metal fiber filter material, and the selection of the catalyst, the configuration of the precursor of the catalyst, the design of the frequency of atomized sample injection and the like should be considered in combination with the preparation requirement of the metal fiber filter material.

In operation S103, the catalyst precursor solution is fed into the plurality of burners 2 using the atomized feed, and the atomized catalyst precursor solution 7 is mixed with the oxidant in the burners 2.

According to an embodiment of the invention, the means for applying the atomized sample includes pulsed atomized sample application, gas impingement.

According to the embodiment of the invention, a pulse atomization sample is adopted, and the precursor solution is atomized by using a pulse nozzle 4 and then fed into the combustor 2, wherein the number of the pulse nozzles 4 can be multiple. The amount of the atomized catalyst precursor solution 7 entering the burner can be controlled by controlling the on-off duration of the pulse nozzle 4.

According to the embodiment of the invention, the concentration stability of the catalyst can be ensured by adopting atomization sampling, so that the finally formed product has uniform shape and stable performance.

According to an embodiment of the present invention, an oxidant enters the burner 2 through the oxidant inlet 5, and is mixed with the atomized catalyst precursor solution 7 in the burner 2.

According to an embodiment of the invention, the oxidizing agent comprises one of: air, oxygen, and a mixture of air and oxygen.

In operation S104, fuel and a bath gas are supplied to the burner 2, and the atomized catalyst precursor solution 7, the oxidant, the fuel, and the bath gas are co-combusted.

According to an embodiment of the invention, the fuel comprises a gaseous fuel or a liquid fuel.

According to an embodiment of the invention, the bath gas comprises nitrogen or an inert gas.

According to an embodiment of the invention, the amount of oxidant entering the combustor 2 is regulated with a first flow controller (not shown); regulating the amount of fuel entering the burner 2 with a second flow controller (not shown); the amount of the bath gas to be introduced into the burner 2 is regulated by a third flow controller (not shown). The structure of the catalyst can be regulated and controlled by controlling the amount of the atomized catalyst precursor solution, oxidant, fuel and bath gas.

According to an embodiment of the invention, each burner 2 comprises a plurality of flame distributors 8, the plurality of flame distributors 8 being evenly distributed in the burner 2.

It should be noted that, by adopting the concept of system integration, the flame distributor and the single burner are organically combined, and the number and distribution mode of the burners and the flame distributor in the single burner can be adjusted according to the production requirements.

In operation S105, the atomized catalyst precursor solution 7 is pyrolyzed to form catalyst nuclei.

In operation S106, the catalyst nuclei are aggregated, grown, and deposited on the metal fiber mat substrate 1.

According to the embodiment of the invention, the catalyst nuclei are gathered and grow to form the catalyst particle layer 9, and the metal fiber felt substrate 1 moves at a certain speed, so that the catalyst particle layer 9 is uniformly deposited on the metal fiber felt substrate 1 to form the metal fiber filter material.

According to the embodiment of the invention, the density of the catalyst load can be regulated and controlled by controlling the integration density of the flame distributor, so that different metal fiber filter materials can be prepared.

According to the embodiment of the invention, the burners can be positioned on two sides of the metal fiber felt substrate, and the burners on the two sides of the metal fiber felt substrate can be controlled to be switched on and off, so that the single-side loading or the simultaneous loading of the catalyst on two sides of the metal fiber felt substrate can be realized. According to an embodiment of the invention, the catalyst is a noble metal, a transition metal or a rare earth metal and oxides thereof having catalytic properties.

According to an embodiment of the invention, the catalyst comprises at least one of: iridium oxide, palladium oxide, ruthenium oxide, rhodium oxide, iron oxide, cerium oxide, aluminum oxide, chromium oxide, barium oxide, zinc oxide, lanthanum cobalt oxide, lanthanum manganese oxide, perovskite.

According to the embodiment of the invention, pulse atomization sampling can be adopted, and the radio frequency and the pulse width of the pulse atomization sampling control the growth rate, the thickness and the stoichiometry of the catalyst, wherein the radio frequency is less than 100Hz, and the pulse width is in millisecond order.

According to embodiments of the present invention, the structure of the catalyst may be controlled by controlling the average deposition rate as well as the deposition time.

Fig. 4 is a schematic structural diagram of a metal fiber filter material provided in an embodiment of the present invention.

As shown in fig. 4, the catalyst produced by pyrolysis of the plurality of flame distributors 8 is uniformly deposited on the metal fiber substrate 1 in the form of a dense lattice of nanoparticles.

In operation S107, the performance of the prepared metal fiber filter material is tested and processed.

According to the embodiment of the invention, the metal fiber filter material deposited with the catalyst particles is further subjected to stacking, forming, ventilation, catalysis and filtration performance detection to form the qualified metal fiber filter material.

According to the embodiment of the invention, the catalyst can be selectively prepared by adhesion according to the VOCs components and the exhaust gas temperature, and different catalyst components are combined and paired to form the catalytic purification metal fiber filter material with corresponding functions.

The invention also provides a metal fiber filter material with the functions of dedusting and catalytic purification of VOCs, which is obtained by the preparation method.

The invention also provides application of the metal fiber filter material in purifying mixed waste gas containing dust and VOCs.

According to the embodiment of the invention, the dust removal mechanism of the metal fiber filter material is that when dust-containing gas passes through the metal fiber filter material, a surface dust layer is rapidly formed on the surface of the metal fiber filter material through screening, interception, collision and electrostatic action at the initial stage, and then dust in mixed waste gas containing dust and VOCs is filtered through the surface dust layer.

The metal fiber filter material provided by the embodiment of the invention can simultaneously purify dust and VOCs gas, and is suitable for treating mixed waste gas containing VOCs gas and dust. The metal fiber felt is not required to be used for carrying out dust removal treatment on the mixed waste gas in advance, and then the catalytic purification reactor is used for carrying out catalytic purification. The efficiency of catalytic purification of mixed waste gas is improved by using the metal fiber filter material provided by the embodiment of the invention.

The preparation method of the metal fiber filter material for catalytic purification of VOCs provided by the embodiment of the invention does not need to prepare a dust facing layer, a buffer layer, a catalytic filter layer and a support layer which are laminated.

The preparation method of the metal fiber filter material for catalytic purification of VOCs provided by the embodiment of the invention can regulate and control the structure of the catalyst by controlling the amount of the atomized catalyst precursor solution, the oxidant, the fuel and the bath gas, and the preparation process is stable and reliable.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.