Fluorescent aerosol, mixed gas and aerosol collection and detection device

Abstract

The present application provides a novel gas tracer, fluorescent aerosol, mixed gas, and aerosol collection and detection device. The novel gas tracer of the present application includes a fluorescent substance and a load material, wherein the fluorescent substance is connected to the load material by physical adsorption or chemical bonding, and the load material is used to prevent fluorescence quenching of the fluorescent substance. The fluorescent aerosol prepared using the novel gas tracer has uniform particle size and high fluorescence intensity, can be suspended in gas for a long time, and after mixing with gas, can be used as a tracer for detecting gas leaks, conveniently and quickly monitoring the sealing of gas reservoirs.

Description

Technical Field

[0001] The present application belongs to the field of tracer detection, and specifically relates to a novel gas tracer, fluorescent aerosol, mixed gas, and aerosol collection and detection device. Background Art

[0002] Currently, some imported or mined natural gas needs to be stored for backup, requiring various types of gas storage facilities. There are four typical types of underground natural gas storage facilities worldwide: depleted oil and gas reservoir storage, aquifer storage, salt cavern storage, and abandoned mine storage. my country's gas storage facilities operate on an annual cycle, employing a "winter-spring gas extraction, summer-autumn gas injection" process.

[0003] Natural gas leakage is a major safety issue facing gas storage facilities, especially in populated areas. Once natural gas leaks or explodes, it will cause serious economic losses and personal injuries. Therefore, detecting whether natural gas storage facilities are leaking is a crucial and necessary task.

[0004] Currently, there are three main methods for detecting natural gas leaks. Method 1: Smell: Before gas is delivered to the end user, an odorant is added to the gas to aid leak detection. Therefore, you can detect a leak by smelling it. Method 2: Apply soapy water: Apply dishwashing liquid or soapy water to the pipe joint or where a "hissing" sound is made. If there is a gas leak, bubbles will appear. Method 3: Check the gas meter: If the gas meter needle moves when the gas is not in use, it can be determined that there is a gas leak. If a gas alarm is installed in the home, it will sound if a gas leak occurs. However, these three methods are only suitable for short-term gas tank leak detection in small gas storage tanks and are not suitable for large gas storage facilities where gas leak detection is frequently carried out over a long period of time.

[0005] Prior art also includes techniques for tracing target gases by atomizing fluorescent materials into aerosols. For example, US Pat. No. 6,392,227 B1 discloses dissolving a fluorescent marker in a solvent. When a solvent-based fluorescent marker liquid is exposed to the heat of vaporization, the solvent tends to flash, leaving behind the fluorescent material. When a water-based fluorescent marker liquid is exposed to the heat of vaporization, the water tends to evaporate, leaving behind the fluorescent material. This allows for clear identification of anomalies or defects that lead to leaks when inspected under radiation of an appropriate wavelength. US Pat. No. 1,057,1356 B2 discloses a method for detecting air leaks in various buildings by atomizing a fluorescent material mixed with a solvent into an aerosol. The aerosol accumulates at the leak point and is illuminated by a light source to produce fluorescence. This method directly uses fluorescent materials as aerosols for gas leak detection. However, after a period of suspension in the gas, the aerosol settles into the liquid or onto sand, where it is absorbed by the liquid or sand, resulting in fluorescence quenching and loss of its gas tracing function. Despite advances in leak detection methods, new gas tracing products and systems are still needed to advance the development of long-term gas leak detection technology for gas storage facilities. Summary of the Invention

[0006] In response to the above technical problems, the present application provides a novel gas tracer, comprising a fluorescent substance and a loading material, wherein the fluorescent substance is bound to the loading material, and the loading material is used to prevent fluorescence quenching of the fluorescent substance.

[0007] Furthermore, the load material is microparticles.

[0008] Furthermore, the particles include at least one of inorganic particles and organic particles.

[0009] Furthermore, the organic particles include at least one of polystyrene, melamine formaldehyde, polymethyl methacrylate, polyamide, and polyaniline; and / or,

[0010] The inorganic particles include at least one of silicon dioxide, zirconium oxide, titanium dioxide, and magnetic ferrosoferric oxide.

[0011] Furthermore, the loading material includes a polymer loading agent and / or an inorganic loading agent.

[0012] Furthermore, the novel gas tracer also includes a solvent.

[0013] Furthermore, the fluorescent substance includes at least one of carbon dots, quantum dots, organic fluorescent dyes, and rare earth fluorescent materials.

[0014] The present application also provides a fluorescent aerosol, which is formed by the above-mentioned novel gas tracer through an aerosol generator.

[0015] The present application also provides a mixed gas, which includes a gas to be traced and the fluorescent aerosol as described above.

[0016] The present application also provides an aerosol collection and detection device for enriching and detecting the above-mentioned fluorescent aerosol, wherein the aerosol collection and detection device comprises at least:

[0017] A main body, used for storing the fluorescent aerosol;

[0018] An aerosol sampler, comprising at least one fan and at least one filter element, wherein the fan is used to guide the fluorescent aerosol to the filter element.

[0019] A fluorescence exciter is used to emit fluorescence to the filter element.

[0020] Beneficial Effects: The novel gas tracer of the present application includes a fluorescent substance and a support material, the fluorescent substance being bound to the support material, and the support material being used to prevent fluorescence quenching of the fluorescent substance. The fluorescent aerosol prepared from this novel gas tracer can be suspended in gas and, after mixing with the gas, used as a tracer for gas leak detection, facilitating rapid monitoring of the containment of gas storage reservoirs. By regularly or irregularly collecting a certain amount of gas near the gas storage reservoir, if fluorescence is detected, it indicates a gas storage leak. This method is simple, and the aerosol is collected and enriched on-site using a filter element in an aerosol collection and detection device. Rapid on-site detection can be achieved using a portable fluorescence detector. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic structural diagram of an aerosol generator for this application;

[0022] Figure 2 This is a schematic structural diagram of an aerosol collection and detection device for this application;

[0023] Figure 3 This is a fluorescence emission spectrum of the aerosol of Example 1 of the present application;

[0024] Figure 4 This is a fluorescence light path diagram observed when the laser flashlight of Example 2 of the present application illuminates the aerosol chamber;

[0025] Figure 5 This is a fluorescence emission spectrum of the aerosol of Example 2 of the present application;

[0026] Figure 6 This is a transmission electron microscopy morphology image of the aerosol of Example 2 of the present application;

[0027] Figure 7 This is a fluorescence emission spectrum of the aerosol of Example 3 of the present application;

[0028] Figure 8 This is a fluorescence emission spectrum of the aerosol of Example 4 of the present application;

[0029] Figure 9 This is a scanning electron microscope morphology image of the aerosol of Example 4 of the present application;

[0030] Figure 10 This is a fluorescence emission spectrum of the aerosol of Example 5 of the present application;

[0031] Figure 11 This is a scanning electron microscope morphology image of the aerosol of Example 5 of the present application;

[0032] Figure 12 This is a fluorescence emission spectrum of the aerosol of Example 6 of the present application;

[0033] Figure 13 This is a schematic diagram of the green light solid powder tracer of Example 7 of the present application;

[0034] Figure 14 This is a fluorescence emission spectrum of the aerosol of Example 7 of the present application;

[0035] Figure 15 This is a graph showing changes in the content of aerosol in gas generated by an aerosol generator in Example 8 of the present application;

[0036] Figure 16 This is a fluorescence light path diagram of the aerosol observed under laser flashlight after the aerosol is settled and then re-suspended by air in Example 8 of the present application. DETAILED DESCRIPTION

[0037] The following will describe the technical solutions in the embodiments of the present application in detail in combination with the embodiments of the present application. It should be noted that the described embodiments are only part of the embodiments of the present application, not all of the embodiments.

[0038] As described in the background art, it is difficult to conduct long-term, continuous and effective gas leakage detection on gas storage facilities in the prior art, which restricts the development of gas tracer detection technology.

[0039] Based on this, the present application provides a new type of gas tracer, including a fluorescent substance and a load material, wherein the fluorescent substance is bound to the load material, and the load material is used to prevent the fluorescent substance from undergoing an aggregation-induced quenching effect. The fluorescent substance is bound to the load material by physical adsorption, hydrogen bonding and / or chemical bonding, so that after the aerosol prepared by the gas tracer settles, the load material will protect the fluorescent substance from quenching, for example, the protection of the load material will prevent the fluorescent substance from undergoing an aggregation-induced quenching effect, so that the fluorescent substance can still emit fluorescence in the absence of a solvent; that is, the load material will protect the fluorescent substance from being adsorbed by the liquid or solid at the bottom of the gas storage reservoir and losing its fluorescence performance. When the external gas conditions change, the aerosol will continue to fly into the gas to play a leak detection role. Even if the aerosol formed by the combination of the fluorescent substance and the load material settles, under certain conditions, such as airflow fluctuations and pressure changes, the settled aerosol will be redispersed and suspended in the gas, which is conducive to long-term and continuous detection of gas leaks.

[0040] In a specific embodiment of the present application, the surface of the load material loaded with fluorescent substance is modified to make the load material hydrophilic or hydrophobic, so that when the aerosol settles to the interface of the water phase or the oil phase, it will not be adsorbed, but float on the interface surface. Under certain conditions, such as air flow fluctuations and pressure changes, the aerosol will be redispersed and suspended in the gas, and will continue to play a gas leak detection role for a long time.

[0041] In a specific embodiment of the present application, the physical adsorption effect is, for example, at least one of electrostatic adsorption and magnetic adsorption, and the physical connection method can be that the fluorescent substance and the load material are combined together to form a gas tracer, for example, mesoporous dendritic silica and carbon dots can be combined by electrostatic adsorption to form a gas tracer.

[0042] In a specific embodiment of the present application, the chemical bond is, for example, at least one of a covalent bond and a coordination bond. The chemical bond can enable the fluorescent substance to be stably connected to the load material. For example, aminosilanized silica particles are connected to carboxyl carbon dots through covalent bonds to form a gas tracer with good stability.

[0043] In a specific embodiment of the present application, the general formula of hydrogen bonds is, for example, X-H...Y, where X and Y represent non-metallic atoms such as F, O, and N with high electronegativity and small atomic radius. The hydrogen bond connection method is low-cost and simple in process. For example, polyvinyl alcohol and carbon dots can be connected by hydrogen bonding to form a gas tracer.

[0044] In a specific embodiment of the present application, the gas tracer is in liquid or powder form, which is convenient for storage and transportation and has high safety. The gas tracer is used to prepare aerosol on-site in the gas storage depot, which can achieve efficient gas leak detection effect.

[0045] In a specific embodiment of the present application, when the gas tracer is a liquid, the solute concentration does not exceed the solubility, and the specific concentration is set as needed.

[0046] In a specific embodiment of the present application, when the gas tracer is a powder, the powder particle size does not exceed 10 μm, so that an aerosol generator can generate an aerosol with good particle size uniformity and good suspension stability in the gas.

[0047] In a specific embodiment of the present application, the weight percentage of the fluorescent substance in the novel gas tracer is 1-30wt%, so that the fluorescent substance can be evenly dispersed on the support material to obtain fluorescent properties. If the weight percentage of the fluorescent substance in the novel gas tracer is too low, the uniformity of the dispersion of the fluorescent substance in the support material is affected, resulting in a portion of the support material being devoid of the fluorescent substance. If the weight percentage of the fluorescent substance in the novel gas tracer is too high, some of the fluorescent substance cannot be loaded by the support material, resulting in the fluorescent substance in the unloaded portion being susceptible to fluorescence quenching. The weight percentage of the fluorescent substance in the novel gas tracer is preferably 5-15wt%, so that the aerosol formed by the novel gas tracer can fully exert its gas leak detection function.

[0048] In one embodiment of the present application, the loading material is microparticles. The fluorescent substance is combined with the gas tracer of the microparticles to obtain an aerosol with good particle size uniformity. The aerosol can float in the gas for a long time, thereby exerting a long-term gas leak detection effect.

[0049] In a specific embodiment of the present application, the microparticles include at least one of inorganic microparticles and organic microparticles. Compared with the aerosol particles in the prior art, which are irregular, easy to collide and agglomerate, and easy to quench fluorescence, the new gas tracer of the present application uses microparticles as the loading material. The aerosol particles prepared by the gas tracer have good particle size uniformity, high dispersion stability, and excellent gas leak detection effect.

[0050] In a specific embodiment of the present application, organic microparticles serving as load materials can be prepared by dispersion polymerization, emulsion polymerization, and bulk polymerization. The preparation method has simple process, a wide source of raw materials, and low cost. It has low performance requirements for fluorescent substances and can be adapted to a variety of different fluorescent substances to obtain new gas tracers.

[0051] In a specific embodiment of the present application, the size of the organic particles used as the load material is 100 to 3000 nm. The organic particles form a load material with good binding properties to the fluorescent substance, which is more conducive to preventing the fluorescent substance in the aerosol prepared by the gas tracer from being adsorbed by solids / liquids and losing its gas leak detection function.

[0052] In a specific embodiment of the present application, the size of the inorganic particles used as the load material is 10 to 2500 nm. It can be understood that the particle size of the present application refers to the distance between the two farthest points on a single particle. The inorganic particles have a small particle size, so the effect of gravity is small. Ultimately, as the main component of the aerosol, the aerosol is suspended in the gas for a long time. Even after the aerosol settles, it is easy to suspend in the gas again when the conditions change, thereby playing a role in gas leak detection.

[0053] In a specific embodiment of the present application, the inorganic particles of the present application are generally surface-modified and then connected to fluorescent substances through, for example, covalent, coordination or physical adsorption. The inorganic particles are easy to modify, have good stability, and have light scattering effects, so that the new gas tracer obtained has good stability and high luminous efficiency.

[0054] In a specific embodiment of the present application, the loading material includes a polymer loading agent and / or an inorganic loading agent, and the polymer loading agent includes at least one of polyvinyl pyrrolidone, polyvinyl alcohol, polyvinylidene fluoride, polyurethane, polyamide, polystyrene, cellulose, and gelatin. The polymer loading agent is easy to prepare and has low cost. The polymer loading agent loads and adsorbs the fluorescent substance through a network structure, thereby obtaining a new gas tracer with good applicability and high stability.

[0055] In a specific embodiment of the present application, the inorganic loading agent includes at least one of fumed silica and salt, and the inorganic loading agent effectively improves the fluorescence performance. Fumed silica is easily modified to be hydrophobic or hydrophilic, and has strong adsorption properties for fluorescent substances. The salt used as the inorganic loading agent of the present application includes at least one of sodium chloride, potassium chloride, sodium sulfate, sodium sulfonate, and potassium phosphate. The fluorescent substance can enter the crystal lattice of the salt, and the salt as a skeleton can effectively protect the fluorescence properties of the fluorescent substance. The inorganic loading agent material is widely available and inexpensive, and the preparation process is simple, economical, green, and low-carbon, which is conducive to large-scale industrial production and preparation.

[0056] In a specific embodiment of the present application, the novel gas tracer of the present application further includes a solvent, which includes at least one of chloroform, ethanol, ethyl acetate, heptane, and water. The solvent can dissolve solutes and will not cause quenching of the fluorescence of the gas tracer. At the same time, it is conducive to storage and transportation. When the novel gas tracer is transported to a gas storage reservoir, the gas tracer can be easily generated into an aerosol by an aerosol generator to play a gas leak detection role.

[0057] In a specific embodiment of the present application, when the novel gas tracer of the present application is a solution, the pH value of the solution is 5 to 9 to avoid affecting the fluorescent luminescence properties of the fluorescent substance.

[0058] In the novel gas tracer of the present application, the fluorescent substance includes at least one of quantum dots, organic fluorescent dyes, and rare earth fluorescent materials. As long as the fluorescent substance can emit fluorescence and will not be instantly quenched, extinguished, or inactivated within a few seconds under conditions of 25-120°C, it can be used to prepare the novel gas tracer, and then the novel gas tracer is used to generate an aerosol for gas leak detection.

[0059] In one embodiment of the present application, the quantum dots include cadmium-based quantum dots, cadmium-free quantum dots, and perovskite quantum dots. Cadmium-free quantum dots are preferred from an environmental perspective. The quantum dots can be prepared by any known method or are commercially available. The quantum dots can include II-VI compounds, III-V compounds, IV-VI compounds, I-III-VI compounds, I-II-IV-VI compounds, perovskite compounds, carbon quantum dots, or combinations thereof. For example, the II-VI group compounds may include: CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, or combinations thereof. The II-VI group compound may further include a Group III metal. The III-V group compound may include GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, InZnP, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, or a combination thereof. The III-V group compound may further include a Group II metal (e.g., InZnP). The IV-VI group compound may include SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, SnPbSTe, or a combination thereof. Examples of the I-III-VI group compound may include CuInSe2, CuInS2, CuInGaSe, and CuInGaS, but are not limited thereto.Examples of the I-II-IV-VI group compound may include, but are not limited to, CuZnSnSe and CuZnSnS. The perovskite quantum dots may be, for example, at least one of CsPbX3 (X=Cl, Br, I) and MAPI (CH3NH3PbI3).

[0060] In a specific embodiment of the present application, the organic fluorescent material is selected from at least one of rhodamine B, lissamine rhodamine B, sodium fluorescein, Nile red, perylene red, tetramethylrhodamine isothiocyanate, 1,3,6,8-pyrene tetracarbonate tetrasodium salt, 9,10-diphenylanthracene, 9,10-bis(phenylethynyl)anthracene, 1-chloro-9,10-bis(phenylethynyl)anthracene, 1,8-dichloro-9,10-bis(phenylethynyl)anthracene, and anthocyanin.

[0061] In a specific embodiment of the present application, the rare earth fluorescent material is mainly composed of rare earth elements (a general term for 17 elements such as the scandium series in Group IIIB of the periodic table), such as oxides of high-purity rare earths such as yttrium, europium, gadolinium, lanthanum, cerium, terbium, and ytterbium.

[0062] In a specific embodiment of the present application, the quantum yield of the fluorescent substance is preferably greater than or equal to 15%, so as to reduce the amount of gas tracer used, shorten the aerosol enrichment time during subsequent leak detection, and facilitate tracer detection in the gas.

[0063] In a specific embodiment of the present application, the size of the fluorescent substance is 1-20 nm, so that the luminescence performance of the prepared fluorescent aerosol is better and the stability in the gas is better.

[0064] The present application also provides a fluorescent aerosol, which is formed by the above-mentioned novel gas tracer through an aerosol generator. The fluorescent aerosol has high stability in the gas and can be dispersed in the gas to be measured for a long time.

[0065] In a specific embodiment of the present application, the size of the fluorescent aerosol is 0.01-10 μm, preferably 0.1-2.5 μm, so that the fluorescent aerosol stays in the gas for a longer time. Even after the fluorescent aerosol settles, under certain conditions of stimulation, the aerosol can fly again and disperse into the gas, so that the aerosol concentration in the gas remains at a high level for a long time.

[0066] In one embodiment of the present application, the concentration of fluorescent aerosol in the gas is as low as 3 μg / m 3 When the color light is detected by human eyes under the excitation light, the solution containing fluorescent aerosol can be detected by fluorescence spectrometer, and the minimum detection limit of fluorescent aerosol concentration can be as low as 1*10 -9 mg / mL, the fluorescent aerosol of the present application is easy to detect.

[0067] In one embodiment of the present application, the aerosol generator comprises a solution aerosol generator or a dry powder aerosol generator. The fluorescent aerosol generated by a solution aerosol generator produces smaller particles, a slower settling rate, and a longer detectable time. The fluorescent aerosol generated by a dry powder aerosol generator has a higher concentration of fluorescent substance, requires a smaller aerosol volume, and reduces operating costs.

[0068] The present application also provides an aerosol generator, such as Figure 1 As shown, the aerosol generator 10 includes a sample pool 1, a nebulization chamber 2, an air compressor 3, a generating chamber 4, and a detector 5. The sample pool 1 is used to place the liquid or powder to be generated into an aerosol. The jet air flow formed by the air compressor 3 is used to spray and atomize the liquid or dry powder in the nebulization chamber 2, and an aerosol is formed in the generating chamber 4. The optical properties of the aerosol are detected by the detector 5.

[0069] In a specific embodiment of the present application, the generating pressure of the aerosol generator is 0.1-1 MPa to prepare fluorescent aerosol with a suitable particle size.

[0070] In a specific embodiment of the present application, the flow rate of compressed air is 10 to 200 L / min to effectively atomize the gas tracer.

[0071] The present application also provides a mixed gas comprising a gas to be traced and the aforementioned fluorescent aerosol. The traced gas can be, for example, at least one of a flammable gas, a non-flammable and non-toxic gas, or a toxic gas. Flammable gases include hydrogen, carbon monoxide, methane, or acetylene; non-flammable and non-toxic gases include nitrogen, oxygen, air, noble gases, carbon dioxide, or nitrous oxide; and toxic gases include nitric oxide, chlorine, or ammonia. The aforementioned aerosol can be easily mixed evenly with the traced gas, allowing the aerosol to effectively detect leaks of the traced gas.

[0072] The present application can be performed by mixing the fluorescent aerosol prepared by the above method with a portion of the gas to be traced, then adding the mixture to a gas storage device to further mix with the gas to be traced in the gas storage device. Alternatively, the fluorescent aerosol can be directly added to the gas storage device to mix with the gas to be traced in the gas storage device, thereby fully utilizing the gas tracing and leak detection function. After the fluorescent aerosol of the present application is mixed with the gas to be traced, the aerosol will be dispersed in the gas to be traced, fully, efficiently, and conveniently utilizing the fluorescent aerosol's tracing and leak detection function for the gas to be traced.

[0073] The present application also provides an aerosol collection and detection device for enriching and detecting the above-mentioned fluorescent aerosol, such as Figure 2The present application discloses an aerosol collection and detection device 11, which includes a main body 6, an aerosol sampler, and a fluorescence exciter 9. The main body 6 is used to store fluorescent aerosols. The aerosol sampler includes at least one fan 8 and at least one filter element 7. The fan is used to guide the mixed gas to the filter element so that the fluorescent aerosol is intercepted by the filter element. The filter element is used to enrich the fluorescent aerosol. The fluorescence exciter is used to excite the aerosol on the filter paper to emit fluorescence, thereby quickly and conveniently determining the location of gas leakage by the appearance of fluorescent areas.

[0074] In a specific embodiment of the present application, the filter element includes at least one of filter paper and filter membrane. The shape of the filter element can be layered, curved or cylindrical. The filter element is detachably designed on the main body. After the aerosol collection is completed, the filter element is disassembled and immersed in a solvent to elute the fluorescent aerosol trapped on the filter element. The treated filter element can be used repeatedly.

[0075] In a specific embodiment of the present application, the aerosol collection and detection device further includes a spectrometer, which is used to detect fluorescence intensity to determine gas leakage.

[0076] The aerosol collection and detection equipment of the present application can achieve the goal of enriching the fluorescent aerosol by using a filter when the content of fluorescent aerosol in the mixed gas is low and difficult to judge with the naked eye, and then perform fluorescence detection on the filter enriched with fluorescent aerosol, thereby achieving the purpose of gas leak detection in the gas storage reservoir.

[0077] The present application conducts fluorescence detection, particle size detection, and concentration detection on the fluorescent aerosol enriched on the filter element to comprehensively judge the gas leakage situation. The aerosol collection and detection device has a compact and simple structure, fast testing, and low cost, and is suitable for large-scale industrial use of fluorescent aerosols in gas storage leak detection.

[0078] Some exemplary embodiments according to the present application are described in more detail below; however, the exemplary embodiments of the present application are not limited thereto.

[0079] Example 1

[0080] Mix 1 mL of 1 mg / mL blue light carbon dot aqueous solution and 10 mL of 10% polyvinyl pyrrolidone aqueous solution to form a homogeneous aqueous solution. Adjust the generation pressure of the aerosol generator to 0.5 MPa, the gas flow rate to 30 L / min, and the evaporation chamber temperature to 80°C. The homogeneous aqueous solution can be generated into an aerosol through the aerosol generator and can be suspended in the air. Use a laser flashlight with an excitation wavelength of 405 nm to illuminate the chamber containing the aerosol, and an obvious blue fluorescent light path can be observed.

[0081] The aerosol is enriched on the filter membrane and soaked in deionized water to disperse the aerosol in the water. The fluorescence emission spectrum of the aerosol can be measured by a spectrometer, such as Figure 3 .

[0082] Example 2

[0083] Red light CdSe / ZnS quantum dots and silica particles are dispersed in chloroform at a mass ratio of 1:2, and the quantum dots are adsorbed onto the silica particles by ultrasound. The quantum dots adsorbed on the surface of the silica particles are then silanized and coated with a layer of silica to obtain quantum dot particles. The particles are washed by centrifugation with ethanol until the supernatant is free of quantum dots. The quantum dot particles are then dispersed in water to obtain a gas tracer aqueous solution. The pressure of the aerosol generator is adjusted to 0.7 MPa, the gas flow rate is 60 L / min, and the evaporation chamber temperature is 100 ° C. The gas tracer aqueous solution is passed through the aerosol generator to generate an aerosol with a size of about 0.3 μm. A laser flashlight with an excitation wavelength of 405 nm is used to illuminate the chamber containing the aerosol, and an obvious red fluorescent light path can be observed, as shown in FIG. Figure 4 .

[0084] After the aerosol is enriched on the filter membrane, the filter membrane is soaked in deionized water to disperse the aerosol in the water. The fluorescence emission spectrum of the aerosol can be measured using a spectrometer, such as Figure 5 The aerosol morphology obtained by transmission electron microscopy is as follows: Figure 6 shown.

[0085] Example 3

[0086] Dendritic silica particles and green-emitting CdSe / ZnS quantum dots were dispersed and mixed in chloroform at a 1:1 mass ratio. The quantum dots adsorbed on the silica particles were then silanized and washed by centrifugation until the supernatant was free of quantum dots to obtain quantum dot microparticles. The quantum dot microparticles were then dispersed in water to create a gas tracer aqueous solution. The aerosol generator was adjusted to a pressure of 0.3 MPa, a gas flow rate of 25 L / min, and an evaporation chamber temperature of 90°C. The gas tracer aqueous solution was passed through the aerosol generator to generate an aerosol approximately 0.15 μm in size. When a laser flashlight with an excitation wavelength of 405 nm was used to illuminate the chamber containing the aerosol, a distinct green fluorescence path was observed.

[0087] After the aerosol is enriched on the filter membrane, the filter membrane is soaked in deionized water to disperse the aerosol in the water. The particle size of the aerosol is measured with a Malvern laser particle size analyzer, and the fluorescence emission spectrum of the aerosol is measured with an F7000 fluorescence analyzer, as shown in FIG. Figure 7 .

[0088] Example 4

[0089] Polystyrene microparticles and red-emitting InP / ZnS quantum dots were dispersed in a 10:1 mass ratio in a 4:1 volume ratio of ethanol and tetrahydrofuran. After stirring, n-hexane was added and stirring continued. The mixture was centrifuged and washed until the supernatant was free of quantum dots to obtain quantum dot microparticles. The quantum dot microparticles were then ultrasonically dispersed in ethanol to create a gas tracer solution. The aerosol generator pressure was adjusted to 0.8 MPa, the gas flow rate to 100 L / min, and the evaporation chamber temperature to 80°C. The gas tracer solution was passed through the aerosol generator to generate an aerosol with a size of 0.35-0.37 μm. When a laser flashlight with an excitation wavelength of 405 nm was used to illuminate the chamber containing the aerosol, a distinct red fluorescent light path was observed.

[0090] The aerosol is enriched on the filter membrane to collect the aerosol, and then the filter membrane is soaked in deionized water to disperse the aerosol into the water. The fluorescence emission spectrum of the aerosol can be measured by a spectrometer. Figure 8 The aerosol morphology measured by scanning electron microscopy is shown in Figure 2. Figure 9 shown.

[0091] Example 5

[0092] A gas tracer solution was prepared by dispersing fumed silica and orange-emitting carbon dots in water at a mass ratio of 1000:1 and stirring to ensure full adsorption of the quantum dots onto the fumed silica. The aerosol generator was adjusted to a pressure of 0.9 MPa, a gas flow rate of 150 L / min, and an evaporation chamber temperature of 120°C. The gas tracer solution was passed through the aerosol generator to generate aerosols with a size of 0.01 to 0.07 μm. A laser flashlight with an excitation wavelength of 405 nm was used to illuminate the aerosol chamber, revealing a distinct orange fluorescent light path.

[0093] After the aerosol is enriched on the filter membrane, the filter membrane is soaked in deionized water to disperse the aerosol into the water. The fluorescence emission spectrum of the aerosol can then be measured using a spectrometer. Figure 10 The aerosol morphology measured by scanning electron microscopy is shown in Figure 11 shown.

[0094] Example 6

[0095] Melamine and formaldehyde are mixed to form a prepolymer. An acidic catalyst containing sodium fluorescein is added to the prepolymer to react and produce melamine-formaldehyde microparticles coated with sodium fluorescein. These melamine-formaldehyde microparticles are collected and dispersed in water to obtain a gas tracer solution. The aerosol generator is set at a pressure of 0.4 MPa, a gas flow rate of 35 L / min, and an evaporation chamber temperature of 100°C. The gas tracer solution is passed through the aerosol generator to generate an aerosol with a size of 0.8-3 μm. A laser flashlight with an excitation wavelength of 405 nm is used to illuminate the chamber containing the aerosol, and a distinct green fluorescent light path is observed.

[0096] After the aerosol is enriched on the filter membrane, the filter membrane is soaked in deionized water to disperse the aerosol in the water, and then the fluorescence emission spectrum of the aerosol is measured using a spectrometer. Figure 12 shown.

[0097] Example 7

[0098] Disperse 1g of fumed silica in 20mL of heptane, and ultrasonicate the fumed silica to form a uniform phase in the heptane. Dissolve 5mg of green carbon dots in the above heptane solution containing fumed silica, stir in the open air to evaporate the solvent, and then wash and centrifuge several times until the supernatant has no fluorescence, and finally obtain a green solid powder tracer, such as Figure 13 The dry powder aerosol generator was set to a pressure of 0.6 MPa, a gas flow rate of 45 L / min, and a motor speed of 300 rpm. A green solid powder tracer was passed through the aerosol generator to generate an aerosol with a size of 0.02 to 0.07 μm. A laser flashlight with an excitation wavelength of 405 nm was used to illuminate the aerosol chamber, and a clear green fluorescent light path was observed.

[0099] After the aerosol is enriched on the filter membrane, the filter membrane is cut into sheets and the fluorescence emission spectrum of the aerosol on the sheet filter membrane can be measured using a spectrometer, such as Figure 14 .

[0100] Example 8

[0101] Fumed silica and red-light CdSe / ZnS were dispersed in heptane at a mass ratio of 20:1 and stirred to ensure full adsorption of the quantum dots onto the fumed silica, creating a gas tracer solution. The aerosol generator was adjusted to a pressure of 0.8 MPa, a gas flow rate of 110 L / min, and an evaporation chamber temperature of 80°C. The gas tracer solution was passed through the aerosol generator to generate an aerosol with a size of 0.25 μm.

[0102] The concentration of the aerosol was detected using a dust meter. After 24 hours, air was blown into the generating chamber again. A laser flashlight with an excitation wavelength of 405 nm was used to illuminate the chamber containing the aerosol. A fluorescent light path was observed, indicating that our aerosol can be redispersed into the air under airflow disturbance after settling. The aerosol of this application has the ability to detect gas leaks for a long time. The concentration change of the aerosol generated by the aerosol generator in the gas is shown in the figure. Figure 15 As shown in Figure 2, after the aerosol settles and is blown into the generating chamber, the fluorescence light path of the aerosol resuspended in the gas is as follows: Figure 16 shown.

[0103] Comparative Example 1

[0104] Vitamin B2 is prepared into a 0.05 mg / mL aqueous solution. The aerosol generator is adjusted to a pressure of 0.2 MPa, a gas flow rate of 8 L / min, and an evaporation chamber temperature of 95°C. Aerosols are generated by the aerosol generator. This aerosol does not directly fluoresce when irradiated with a UV lamp at an excitation wavelength of 405 nm. Fluorescence is only observed in a water-containing medium or when redissolved in water. Once the aerosol comes into contact with water, it dissolves or, once deposited on a solid, is adsorbed to the solid surface, preventing it from redispersing into the gas under airflow to perform its gas leak detection function.

[0105] The fluorescent aerosol concentration involved in Examples 1 to 8 and Comparative Example 1 of the present application was tested using a dust meter, the aerosol morphology was measured using a Hitachi 8100 scanning electron microscope and a FEI Tecnai F20 field emission transmission electron microscope, the aerosol particle size was measured using a Malvern laser particle size analyzer, and the fluorescence emission spectrum was tested using an F7000 fluorescence spectrometer.

[0106] Compared with Comparative Example 1, the fluorescent aerosols prepared by the new gas tracers of Examples 1 to 8 of the present application have uniform particle size, high fluorescence intensity, good stability, and high detection sensitivity. Even if the fluorescent aerosol settles in the gas bin, when air is blown into the gas bin, the fluorescent aerosol will be able to be re-suspended in the gas and play a long-term gas leak detection role. That is, when gas reservoir leak detection is required, the airflow is first disturbed by operations such as blowing, so that the aerosol is dispersed and suspended in the gas again, and then the aerosol leak detection test is performed. The new gas tracer of the present application facilitates efficient and rapid leak detection in various gas reservoirs.

[0107] Although the inventors have elaborated and enumerated the technical solutions of the present application in detail, it should be understood that it is obvious for those skilled in the art to modify and / or adapt the above embodiments or adopt equivalent alternatives, which cannot deviate from the essence of the spirit of the present application. The terms appearing in the present application are used to explain and understand the technical solutions of the present application and cannot constitute a limitation on the present application.

Claims

1. A fluorescent aerosol, characterized in that: The fluorescent aerosol is formed by a gas tracer through an aerosol generator. The gas tracer includes: a fluorescent substance, a load material and a solvent. The fluorescent substance is bound to the load material, and the load material is used to prevent the fluorescent substance from undergoing fluorescence quenching. The fluorescent substance includes at least one of carbon dots, quantum dots, organic fluorescent dyes, and rare earth fluorescent materials. The load material is a particle, and the particle includes at least one of inorganic particles and organic particles. The organic particles include at least one of polystyrene, melamine formaldehyde, polymethyl methacrylate, polyamide, and polyaniline. The inorganic particles include at least one of silicon dioxide, zirconium oxide, titanium dioxide, and magnetic ferrosoferric oxide. The size of the inorganic particles is 10-2500 nm, and the size of the organic particles is 100-3000 nm. The size of the fluorescent aerosol is 0.01-10 μm.

2. A mixed gas, characterized in that: The mixed gas includes a gas to be traced and the fluorescent aerosol as claimed in claim 1 .

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