Gas purification method for three-dimensional printing and 3D printing system

Abstract

The invention relates to the technical field of 3D printing, and discloses a gas purification method for three-dimensional printing and a 3D printing system. The gas purification method comprises the steps that a target space is provided, and a printing material for three-dimensional printing is arranged in the target space, so that the target space comprises target gas derived from the printing material; arranging a photocatalytic device in the target space; projecting light with a predetermined wavelength to the photocatalytic converter to excite the photocatalytic converter; inputting oxygen into the target space to improve the concentration of the oxygen in the target space; and inputting ozone into the target space and / or generating ozone in the target space. The gas purification device aims at solving the problem of air pollution generated in the 3D printing process, and particularly aims at efficient purification of harmful gas such as VOCs (volatile organic compounds).

Description

Technical Field

[0001] The present application relates to the field of 3D printing technology, and in particular to a gas purification method and a 3D printing system for three-dimensional printing. Background Art

[0002] 3D printing is a rapid prototyping manufacturing technology that converts materials such as resin, plastic, and metal from digital models in computers into physical models by building objects layer by layer. 3D printing processes include: Stereolithography (SLA), which uses photosensitive resin as the material and uses UV laser to scan the liquid resin to solidify and shape it layer by layer; Digital Light Processing (DLP), which uses a light source to irradiate the liquid photosensitive resin in the form of a pattern to solidify and shape it layer by layer; Selective Laser Sintering (SLS), which uses powdered metal as the material and uses a laser to scan and irradiate the powder under the control of a computer to achieve the sintering of the material; Fused Deposition Modeling (FDM), which heats and melts the filamentary hot-melt material, extrude the material through a nozzle, and the molten filament is bonded to the previous layer of material to form a shape, etc.

[0003] For 3D printing equipment that uses photosensitive resins or hot-melt plastics as printing materials, these materials will inevitably release volatile gases during the placement or printing process. These gases may contain hydrocarbons, halogenated hydrocarbons, aldehydes, ketones, esters, alcohols and amides, collectively referred to as volatile organic compounds (VOCs). Due to the different properties of VOCs and the toxicity of some components, they may pollute the environment of the printing space and cause potential harm to the health of operators.

[0004] With the increasing popularity of 3D printing technology, the problem of air pollution caused by printing materials (such as in the printing area and inside the printer) has become increasingly prominent. The 3D printing equipment currently on the market uses activated carbon filter adsorption or negative pressure exhaust to exhaust the gas in the printing equipment to the outside to deal with the harmful gases generated during the printing process. However, the activated carbon filter will fail due to saturated adsorption after a period of time, and the filter needs to be replaced frequently to maintain the purification effect; for confined spaces, using negative pressure exhaust to exhaust the internal gas of the printing equipment to the outside (for example, in the room used for manufacturing) still poses a health threat to the operator. Therefore, it is necessary to explore an efficient and sustainable air purification solution to reduce or eliminate the health risks (for example, breathing, allergies, and carcinogenicity) of users when operating printing equipment. Summary of the invention

[0005] In view of the above problems, the present application provides a gas purification method and a 3D printing system for 3D printing, aiming to solve the problems of low air purification efficiency and poor sustainability in the 3D printing industry.

[0006] In a first aspect, an embodiment of the present application provides a gas purification method for three-dimensional printing, comprising: providing a target space, in which printing material for three-dimensional printing is arranged, so that the target space includes a target gas originating from the printing material; arranging a photocatalyst in the target space; projecting light of a predetermined wavelength to the photocatalyst to excite the photocatalyst; inputting oxygen into the target space to increase the concentration of oxygen in the target space; and inputting ozone into the target space and / or generating ozone in the target space.

[0007] The embodiment of the present application proposes a gas purification method based on the catalytic oxidation principle of a photocatalyst, which aims to solve the problem of air pollution generated during the 3D printing process, especially for the efficient purification of harmful gases such as VOCs (volatile organic compounds). The method injects oxygen into the target space inside or around the 3D printing equipment to accelerate the decomposition of VOCs under light and catalyst conditions, and injects ozone to promote the oxidation of small molecule products obtained by decomposition, so that they are converted into harmless substances such as water and carbon dioxide, thereby significantly reducing the concentration of harmful gases in a short time and improving the safety of the 3D printing environment. In addition, since the photocatalyst is not consumed during the reaction process and the substances finally generated are harmless, the technical solution also shows good sustainability and environmental friendliness.

[0008] In some embodiments, the target space is configured to accommodate at least one three-dimensional printing device; or is defined by a single three-dimensional printing device.

[0009] In some embodiments, the three-dimensional printing device includes any one of a DLP printing device, an LCD printing device, an FDM printing device, an SLA printing device, and an inkjet 3D printing device.

[0010] In some embodiments, the photocatalyst includes at least one of titanium dioxide, zinc oxide, tungsten trioxide, and modified titanium dioxide.

[0011] In some embodiments, the modified titanium dioxide comprises at least one of non-metal-doped titanium dioxide, metal-doped titanium dioxide, noble metal-deposited titanium dioxide, and heterostructured titanium dioxide.

[0012] In some embodiments, the predetermined wavelength of light includes visible light and / or ultraviolet light.

[0013] In some embodiments, a first light source is used to emit visible light; and / or a second light source independent of the first light source is used to emit ultraviolet light.

[0014] In some embodiments, the light of predetermined wavelength includes at least one wavelength selected from the following ranges: 190nm-280nm, 281nm-320nm, 321nm-400nm, for example, 240nm-260nm, 310nm-320nm, 340nm-360nm.

[0015] In some embodiments, inputting oxygen into the target space includes: continuously or intermittently inputting oxygen into the target space at a predetermined flow rate to promote decomposition of organic compounds in the target gas.

[0016] In some embodiments, inputting oxygen into the target space includes: using an oxygen supply device to output oxygen of a predetermined concentration to the target space, where the predetermined concentration is 25% to 100%.

[0017] In some embodiments, inputting oxygen into the target space includes: inputting oxygen toward the photocatalyst so that 0.5 m 3 The average oxygen concentration in the space is 28% to 70%.

[0018] In some embodiments, inputting oxygen into the target space includes: inputting oxygen into the target space so that a 5 m 3 The average oxygen concentration in the space is 30% to 50%, for example, 30% to 45%, for example, 35% to 40%.

[0019] In some embodiments, inputting ozone into the target space and / or generating ozone in the target space includes: using light of a predetermined wavelength to decompose oxygen in the target space to obtain ozone; and / or using electric current to decompose oxygen in the target space to obtain ozone; and / or inputting ozone independent of the target space into the target space.

[0020] In some embodiments, the concentration of oxygen and the concentration of ozone input into the target space are configured such that the concentration of the target gas and the concentration of ozone in at least a portion of the target space are both 0 to 0.050 mg / m 3 , preferably 0 to 0.005 mg / m 3 .

[0021] In some embodiments, the gas purification method further comprises: using a ventilation device to accelerate the flow of gas in the target space.

[0022] In some embodiments, the gas purification method further includes: detecting the concentration of a target gas associated with the printing material in the target space; and projecting light of a predetermined wavelength toward the photocatalyst when the detected concentration of the target gas is greater than a first predetermined concentration.

[0023] In some embodiments, the gas purification method further includes: detecting the concentration of a target gas associated with the printing material in the target space; when the detected concentration of the target gas is less than a second predetermined concentration, stopping projecting light of a predetermined wavelength, and stopping inputting and / or generating ozone.

[0024] In some embodiments, the gas purification method further includes: collecting or removing the gas after purification and / or the product obtained by purifying the gas.

[0025] In a second aspect, an embodiment of the present application provides a 3D printing system, including a 3D printing device and a gas purification device, wherein the gas purification device is arranged in a target space associated with a printing material of the 3D printing device, and the gas purification device includes:

[0026] A photocatalyst unit, comprising a photocatalyst;

[0027] a light source assembly configured to project light of a predetermined wavelength toward the photocatalyst to excite the photocatalyst to perform a catalytic reaction;

[0028] an oxygen supply device configured to input oxygen into the target space to increase the concentration of oxygen in the target space; and

[0029] The ozone supply device is configured to input ozone into the target space or generate ozone in the target space.

[0030] In some embodiments, the 3D printing system further includes a ventilation device for accelerating the flow of gas in the target space.

[0031] In some embodiments, the oxygen supply comprises a molecular sieve.

[0032] In some embodiments, the gas purification device includes a shell, which defines a gas passage connected to the target space. The shell is provided with an air inlet for airflow into the gas passage and an air outlet for airflow out of the gas passage. The photocatalyst is arranged in the gas passage.

[0033] In some embodiments, the photocatalyst includes at least one of titanium dioxide, zinc oxide, tungsten trioxide, and modified titanium dioxide;

[0034] And / or, the photocatalyst unit further comprises a carrier for carrying the photocatalyst, and the photocatalyst is arranged on the carrier;

[0035] And / or, the light source assembly is an ultraviolet light source.

[0036] In some embodiments, the modified titanium dioxide comprises at least one of: non-metal doped titanium dioxide, metal doped titanium dioxide, noble metal deposited titanium dioxide, heterostructured titanium dioxide.

[0037] In some embodiments, the 3D printing system further includes a detection unit and a controller, wherein:

[0038] The detection unit is used to detect the concentration of the target gas in the target space;

[0039] The controller is respectively connected to the light source assembly, the ozone supply device, the oxygen supply device and the detection unit for communication; the controller is used to control the light source assembly, the ozone supply device and the oxygen supply device according to the concentration of the target gas.

[0040] In some embodiments, the detection unit includes an ozone sensor for detecting ozone content.

[0041] In some embodiments, the three-dimensional printing device has a closed target space; or

[0042] The target space accommodates at least one three-dimensional printing device.

[0043] In some embodiments, the 3D printing system further includes an exhaust gas treatment device, which is used to collect or remove products obtained by purifying the target gas and / or gases after purification.

[0044] In some embodiments, in a 3D printing system, the gas purification device is bonded to the three-dimensional printing device; or the gas purification device is snap-connected to the three-dimensional printing device; or the gas purification device is magnetically connected to the three-dimensional printing device; or the gas purification device is carried by the three-dimensional printing device.

[0045] In a third aspect, the present application provides a gas purification method for three-dimensional printing, which includes: providing a target space, in which printing materials for three-dimensional printing are arranged; arranging a photocatalyst in the target space; projecting light of a predetermined wavelength to the photocatalyst to excite the photocatalyst; and inputting and / or generating a predetermined concentration of ozone in the target space. In some scenarios, the decomposition of VOCs related to the printing materials can be achieved through the photocatalyst and oxygen in the air. At this time, the introduction of ozone can oxidize the small molecular products after decomposition, thereby reducing the irritation of the related gases to the staff.

[0046] In some embodiments, inputting ozone of a predetermined concentration into a target space and / or generating ozone in a target space includes: using light to decompose oxygen in the target space to obtain ozone; or using electric current to decompose oxygen in the target space to obtain ozone; or using an ozone supply device to output ozone to the target space.

[0047] In some embodiments, the gas purification method further includes: inputting oxygen of a predetermined concentration into the target space to increase the oxygen concentration in the target space.

[0048] In some embodiments, inputting a predetermined concentration of oxygen into the target space includes: inputting oxygen into the target space so that 1 m 3 or 3m 3 The average oxygen concentration in the space is 30% to 45%.

[0049] In some embodiments, inputting a predetermined concentration of oxygen into the target space includes: using an oxygen supply device to output a predetermined concentration of oxygen to the target space, wherein the predetermined concentration is 30% to 90%.

[0050] In some embodiments, the concentration of oxygen and the concentration of ozone input into the target space are configured such that the concentration of the target gas and the concentration of ozone in at least a portion of the target space are both 0 to 0.060 mg / m 3 , preferably 0 to 0.010 mg / m 3 .

[0051] In a fourth aspect, the present application provides a 3D printing system, which includes a three-dimensional printing device and a gas purification device, the gas purification device is arranged in a target space associated with a printing material of the three-dimensional printing device, and the gas purification device includes: a photocatalyst unit, including a photocatalyst; a light source assembly, configured to project light of a predetermined wavelength to the photocatalyst; and an ozone supply device, configured to introduce ozone into the target space or generate ozone in the target space.

[0052] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0054] Figure 1 A schematic diagram of the structure of a gas purification device provided in one of the embodiments of the present application;

[0055] Figure 2 A schematic diagram of the structure of a gas purification device provided in another embodiment of the present application;

[0056] Figure 3 A schematic diagram of the structure of a gas purification device provided in yet another embodiment of the present application;

[0057] Figure 4A schematic diagram of the structure of a gas purification device provided in yet another embodiment of the present application;

[0058] Figure 5 A schematic diagram of the locations of a three-dimensional printing device and a gas purification device provided in one embodiment of the present application;

[0059] Figure 6 A schematic diagram of the locations of a three-dimensional printing device and a gas purification device provided in another embodiment of the present application;

[0060] Figure 7 for Figure 6 A schematic diagram of a cutaway structure of a gas purification device;

[0061] Figure 8 A schematic diagram of a connection method between a gas purification device and a three-dimensional printing device provided in an embodiment of the present application;

[0062] Fig. 9 A schematic diagram of a 3D printing system provided for one embodiment of the present application;

[0063] Fig.10 A flow chart of an air purification method according to some embodiments of the present application;

[0064] Fig.11 This is a flow chart of an air purification method according to some embodiments of the present application.

[0065] The reference numerals in the specific implementation manner are as follows:

[0066] 10. Housing; 11. Air inlet; 12. Air outlet; 13. Gas passage; 30. Photocatalyst; 40. Light source assembly; 41. Light source; 42. Driving circuit; 50. Ozone supply device; 60. Detection unit; 70. Controller; 80. Oxygen supply device; 90. Ventilation device; 100. Gas purification device; 200. Three-dimensional printing equipment; 210. Forming space; 300. Air guide assembly; 400. Waste gas treatment device; 510. Fastener; 520. Adhesive; 530. Magnetic element; 540. Fastener; 600. Target space; 700. Target gas; 900. 3D printing system; 930. Gas purification device; 910. Three-dimensional printing equipment; 920. Three-dimensional printing equipment. DETAILED DESCRIPTION

[0067] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0068] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0069] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0070] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0071] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0072] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0073] In the description of the embodiments of the present application, the orientations or positional relationships indicated by the technical terms "lateral", "upper", "lower", "left", "right", "bottom", "inside" and "outside" are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the embodiments of the present application and simplifying the description. They do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0074] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0075] In the field of 3D printing, the printing materials used often contain high concentrations of volatile organic compounds (VOCs). The concentration of VOCs gas released by the printing materials during storage and use is much higher than that of conventional air purification scenarios. Conventional air purification scenarios are the purification and filtration of harmful gases such as indoor formaldehyde, VOCs, PM2.5 dust particles, etc., whose concentration in the space is not high and do not require efficient purification rates. Most products achieve slow purification by using gas external circulation exchange. However, in the application scenarios of 3D printing, printing consumables will release high concentrations of VOCs gas in a short period of time during natural storage and printing. For example, in photocuring 3D printing, due to the complex components of liquid photocuring resin, even in the process of static storage, complex VOCs gas will be volatilized; in the process of 3D printing, due to the movement and stirring of the molding platform and the heating function of the tray containing resin materials in some 3D printing equipment, the volatilization of VOCs gas will be accelerated, resulting in a rapid decline in the air quality around the equipment and even the entire space. The same is true for 3D printing devices 200 with other molding processes. For example, during the printing process, the FDM 3D printing device 200 needs to melt the thermoplastic material at a high temperature, which will also release a large amount of harmful gases in a short period of time, which may endanger the health of the operator. Therefore, in view of the air purification needs of the 3D printing environment, not only a higher purification efficiency is required, but also the concentration of harmful gases such as VOCs needs to be significantly reduced in a shorter time to ensure the health and safety of the operators.

[0076] Based on this, the present application embodiment proposes a gas purification method for three-dimensional printing, combined with the attached Figure 1 ,include:

[0077] Providing a target space 600, the target space 600 is associated with a printing material for three-dimensional printing;

[0078] Arranging a photocatalyst 30 in the target space 600;

[0079] Projecting light of a predetermined wavelength toward the photocatalyst 30 to excite the photocatalyst to perform a catalytic reaction; and

[0080] Ozone of a predetermined concentration is introduced and / or generated into the target space 600 for a decomposition reaction.

[0081] The printing materials used for three-dimensional printing include, but are not limited to, photosensitive resins, ABS wires, PLA wires, nylon, photocurable inks, and other consumable materials used in the three-dimensional printing device 200. Among them, photosensitive resin refers to a resin material that can be cured under ultraviolet light or other light sources, and epoxy resins and the like can be listed. The full name of ABS wire is acrylonitrile-butadiene-styrene (Acrylonitrile Butadiene Styrene) copolymer. PLA wire refers to polylactic acid material. Since the above-mentioned printing materials will inevitably produce volatile gases during the placement or printing process, the "target space 600" associated with the above-mentioned printing materials will have air pollution problems. The "target space 600" here includes, but is not limited to, the interior and surroundings of the three-dimensional printing device 200.

[0082] The term "photocatalyst 30", also called photocatalyst, is a general term for semiconductor materials with photocatalytic function represented by titanium dioxide. As in the embodiment, the photocatalyst 30 is commonly used N-type semiconductor material, which has the characteristics of low bandgap width, and can produce strong oxidizing substances (such as hydroxyl radicals, oxygen, etc.) under light irradiation, and can be used to decompose organic compounds, some inorganic compounds, bacteria and viruses, etc. The photocatalyst 30 includes but is not limited to semiconductor compound materials such as titanium dioxide, zinc oxide, and tungsten oxide, and also includes modified materials obtained by doping, compounding, coating and other process methods based on such compounds.

[0083] The light of the predetermined wavelength refers to the excitation light that can excite the photocatalyst 30 to produce catalytic activity. The wavelength selection of the light is diverse and can be freely selected from visible light to ultraviolet light (including UVA, UVB and UVC bands) according to the matching degree of the selected photocatalyst 30.

[0084] In the embodiment of the present application, the photocatalyst 30 is used to stimulate a catalytic reaction under the irradiation of light of a preset wavelength to decompose organic pollutants, including VOCs, generated during the placement or printing process of the printing material. By introducing or generating ozone in the target space 600, the decomposition products of the VOCs gas can be oxidized, thereby meeting the higher purification efficiency required in the field of three-dimensional printing. This method can significantly reduce the concentration of harmful gases such as VOCs in a very short time.

[0085] In a specific embodiment of the present application, taking the titanium dioxide photocatalyst 30 as an example, the following is a simplified reaction equation for the catalytic decomposition of VOCs by TiO2:

[0086] TiO2+hv→TiO2*+h + +e-

[0087] O2+e - → O2 -

[0088] h + +H2O→H + + OH

[0089] O2 - +H + → HO2

[0090] O2 - +·O2 - →H2O2+O2

[0091] O2 - + HO2 → HO2 - +O2

[0092] HO2 - +H + →H2O2

[0093] H2O2+e - → OH+OH -

[0094] H2O2+·O2 - → OH+OH - +O2

[0095] H2O2+hv→2·OH

[0096] Here hv represents the energy of the photon, TiO2* represents the excited state of titanium dioxide, and e - and h + represent free electrons and holes respectively.

[0097] Then, VOCs are oxidized by the action of electron-hole pairs:

[0098] VOCs+h + →Intermediate products

[0099] Finally, the intermediates are further oxidized (e.g., by ozone) to produce carbon dioxide and water:

[0100] Intermediate product →CO2+H2O

[0101] From the chemical equation of the above catalytic reaction, it can be seen that the photocatalyst 30 is activated under the action of light to produce active substances with strong oxidizing properties, such as OH· (hydroxyl radicals). These active substances can efficiently oxidize organic matter in the exhaust gas. The active substances react with organic matter (VOCs) in the exhaust gas to cause the breakage of the C=C bond (carbon-carbon double bond) and the formation of a new C=O bond (carbon-oxygen double bond). In this process, the organic matter is gradually decomposed into small molecules and finally converted into inorganic matter. However, during the catalytic reaction of the photocatalyst 30, VOCs harmful substances are often not completely decomposed into harmless components such as water and carbon dioxide directly, but at least part of them are first opened to generate new small molecular organic intermediates by opening the macromolecular bonds of the macromolecular VOCs, and these intermediates are further converted into harmless substances through subsequent redox reactions. If the small molecular intermediates produced are not completely decomposed during the purification reaction, new pollutants such as irritating odors will be produced. The addition of ozone can solve this problem. The strong oxidizing ability of ozone can further convert the produced intermediate small molecular products into harmless substances such as water and carbon dioxide. Although ozone is also one of the intermediate products in the catalytic reaction of the photocatalyst 30 (UV photolysis of oxygen produces a small amount of ozone), the content is extremely low and is not enough to fully decompose the intermediate product into water and carbon dioxide. Introducing or generating ozone into the target space 600 can further promote the purification reaction to achieve a better purification effect.

[0102] In some embodiments, the target space 600 is configured to accommodate at least one 3D printing device 200 ; alternatively, the target space 600 is defined by a single 3D printing device 200 .

[0103] Here, the target space 600 can be independently applied to 3D printing scenarios of different scales, such as a small laboratory to a large 3D printing farm (including a large number of 3D printing devices 200); it can also be used in combination with the 3D printing device 200, such as being arranged in the printing area of ​​the 3D printing device 200; it can also be embedded as a module inside the 3D printing device 200. The target space 600 has high adaptability and integration.

[0104] In some embodiments, the three-dimensional printing device 200 includes any one of a DLP printing device, an LCD printing device, an FDM printing device, an SLA printing device, and an inkjet printing device (eg, “MJP” technology).

[0105] Among them, the terms "DLP printing device", "LCD printing device", "FDM printing device", "SLA printing device" and the like all refer to different types of 3D printing or printing technologies. For example: DLP printing device (Digital Light Processing) uses digital light processing technology to project images onto photosensitive resin through a projector, and solidifies layer by layer to form a 3D model; LCD printing device (Liquid Crystal Display) uses an LCD screen as a light source and solidifies the resin by controlling the pixels on the LCD screen; FDM printing device (Fused Deposition Modeling) uses fused deposition modeling technology to melt the plastic filament by heating the nozzle and then accumulate it layer by layer to form a 3D model. SLA printing device (Stereolithography Apparatus) uses stereolithography technology to use lasers to solidify photosensitive resin layer by layer to form a 3D model. The above-mentioned three-dimensional printing devices 200 have different structural compositions according to different molding processes. The same thing is that they all have printing molding space and consumables storage space, and the various mechanisms cooperate with each other to mold the printing materials into printed parts. During the printing process, the volatilization of the printing material itself and the movement and heating of the printing mechanism accelerate the volatilization of the printing material, resulting in high concentrations of VOCs organic pollutants inside and around the 3D printing device 200, which may cause discomfort to the operator and pollute the environment. The air purification method of the embodiment of the present application can efficiently decompose and purify the harmful gases generated by the above 3D printing device 200.

[0106] In some embodiments, the photocatalyst 30 includes at least one of titanium dioxide, zinc oxide, tungsten trioxide, and modified titanium dioxide.

[0107] The properties of the photocatalyst 30 largely determine its ability and efficiency to purify VOCs after excitation. The above-mentioned photocatalyst 30 has high catalytic efficiency and can significantly improve the ability and efficiency of the purification reaction. Among them, the modified titanium dioxide is modified by doping, coating or composite materials, which improves the light absorption capacity and catalytic activity of the photocatalyst material, thereby further improving the ability and efficiency of the purification reaction.

[0108] In some embodiments, the modified titanium dioxide comprises at least one of non-metal-doped titanium dioxide, metal-doped titanium dioxide, noble metal-deposited titanium dioxide, and heterostructured titanium dioxide.

[0109] The modified titanium dioxide photocatalyst 30 has a higher catalytic efficiency. The modified photocatalyst 30 has the advantages of being more easily excited by light and less prone to ion recombination, and can produce more active species in the catalytic reaction and prolong its life, thereby having better purification capacity and purification efficiency. As an example:

[0110] Non-metal-doped titanium dioxide can be listed as carbon-doped titanium dioxide, nitrogen-doped titanium dioxide, fluorine-doped titanium dioxide, etc., which can improve the conductivity of titanium dioxide, thereby further improving the photocatalytic efficiency;

[0111] Metal-doped titanium dioxide can be listed as copper-doped titanium dioxide, iron-doped titanium dioxide, manganese-doped titanium dioxide, etc., which can increase the light absorption of titanium dioxide, thereby further improving the photocatalytic efficiency;

[0112] Precious metal deposited titanium dioxide can be listed as: silver deposited titanium dioxide, platinum deposited titanium dioxide, gold deposited titanium dioxide, etc., which can change the lattice structure of titanium dioxide, thereby further improving the photocatalytic efficiency;

[0113] Heterostructured titanium dioxide includes composite materials of titanium dioxide and bismuth oxide, etc. Such materials can inhibit the recombination of electron-hole pairs, thereby further improving the photocatalytic efficiency.

[0114] In some embodiments, the light of the predetermined wavelength includes visible light and / or ultraviolet light. The wavelength of the ultraviolet light may be 180 nm to 410 nm. As an example, the wavelength of the ultraviolet light may be 180 nm, 185 nm, 254 nm, 365 nm, 385 nm, 405 nm, 410 nm, etc., which are typical but non-limiting values. Light of different wavelengths may also be mixed to achieve a better purification effect.

[0115] In some embodiments, the wavelength of the ultraviolet light is 190 nm to 280 nm, for example, 190 nm to 240 nm. Ultraviolet light within this wavelength range can be used to excite photocatalyst materials and can also be used to decompose oxygen into ozone.

[0116] The wavelength of ultraviolet light is shorter and the energy is higher. The photocatalyst material excited by ultraviolet light has higher catalytic activity and can decompose harmful substances faster. Generally, the shorter the wavelength of UV light, the higher the energy, and the easier it is to excite the photocatalyst to produce purified ions. As an example, the wavelength of ultraviolet light can be 190nm, 210nm, 220nm, 230nm, 240nm, 254nm, 260nm, 270nm, 280nm and other typical but non-limiting values.

[0117] In some embodiments, introducing and / or generating a predetermined concentration of ozone into the target space 600 includes: using light of a predetermined wavelength to decompose oxygen in the target space 600 to obtain ozone.

[0118] When the predetermined wavelength of light is ultraviolet light with a wavelength between 240nm and 310nm, when ultraviolet light in this wavelength range irradiates oxygen molecules (O2) in the atmosphere, these molecules absorb enough energy to decompose into two oxygen atoms (O). This process is called photolysis or photochemical decomposition. The oxygen atoms produced in this process are very active and they will quickly react with other oxygen molecules to form ozone molecules (O3).

[0119] In some embodiments, introducing and / or generating a predetermined concentration of ozone into the target space 600 includes: using an electric current to decompose oxygen in the target space 600 to obtain ozone.

[0120] Methods for using electric current to decompose oxygen in the target space 600 to generate ozone may include a corona discharge method and an electrochemical method. The corona discharge method causes the gas to undergo a corona discharge phenomenon under high voltage conditions, thereby forming a plasma, which further acts on oxygen molecules to cause them to decompose and recombine into ozone. The electrochemical method uses a direct current power supply to electrolyze an electrolyte solution containing oxygen, and directly generates ozone through an electrode reaction.

[0121] The method of using electric current to decompose oxygen to generate ozone can efficiently convert oxygen into ozone, which not only accelerates the ozone generation rate, but also significantly improves the yield. In particular, they provide more controllable production conditions, allowing operators to accurately adjust the amount of ozone generated according to actual needs, improving production flexibility and efficiency.

[0122] In some embodiments, the gas purification method further includes inputting oxygen of a predetermined concentration into the target space 600 to increase the concentration of oxygen in the target space 600 .

[0123] The photocatalyst 30 does not consume its own substances during the purification process but acts as a catalyst, but the O2 in the reaction space actually participates in the reaction. Therefore, in order to meet the higher purification rate requirements of VOCs harmful gases in the 3D printing scene, a predetermined concentration of oxygen can be input into the target space 600 to create an oxygen-rich purification environment to improve the decomposition efficiency.

[0124] In some embodiments, a predetermined concentration of oxygen is input into the target space to make the oxygen concentration in the target space 600 be 25% to 50%. 3 or 1.0m 3 or 2.0m 3 or 3.0m 3or 5.0m 3 In the space, the average oxygen concentration is 25% to 50%, such as 28% to 45%, such as 35% to 40%. The oxygen supply device can also output a predetermined concentration of oxygen, such as 25% to 100%, such as 30% to 90%, such as 40% to 80%. The oxygen supply device can supply oxygen at a predetermined flow rate, and the setting of the flow rate takes into account the size of the target space.

[0125] In some embodiments, the concentration of oxygen and the concentration of ozone input to the target space are configured such that: at least a portion of the target space (for example, the target space is 100m 3 , detect a space of 2m at one point 3 The concentration of the target gas and the concentration of ozone in the gas concentration are both 0 to 0.060 mg / m 3 , for example 0.005~0.010mg / m 3 , for example 0.006~0.050mg / m 3 .

[0126] When the printing material is a photosensitive resin, the cross-linking reaction of the printing material is affected by oxygen. At this time, the oxygen concentration in the target space defined by a single printing device needs to be controlled, for example, 20% to 50%, such as 30% to 40%.

[0127] As an example, the oxygen concentration in the target space 600 may be 30%, 32%, 34%, 36%, 38%, 40%, 42%, 44%, 46%, 48%, 50%, etc. Typical but non-limiting values. Properly increasing the oxygen concentration in the target space 600 helps to supplement the oxygen components required for the decomposition reaction of VOCs (volatile organic compounds), thereby improving the purification efficiency and better meeting the demand for rapid purification in the 3D printing process.

[0128] However, in some scenarios, if the oxygen concentration is too high, the quality of the printed product may be affected due to the oxygen inhibition effect of the photocurable resin. Therefore, by accurately controlling the oxygen concentration in the target space 600 between 30% and 50%, the quality of the 3D printing can be maintained and a higher purification efficiency can be achieved.

[0129] In some embodiments, the gas purification method further includes: accelerating the flow of the gas in the target space 600 using the ventilation device 90 .

[0130] The ventilation device 90 includes but is not limited to a fan, a blower and an exhaust system. The fan may be an axial flow fan, a centrifugal fan or a DC brushless fan. The function of the ventilation device 90 is to promote the gas circulation in the reaction space so that the gas containing high concentrations of harmful components of VOCs can flow evenly and fully through the surface of the photocatalyst 30, thereby further improving the purification rate of the reaction area.

[0131] In some embodiments, the gas purification method further includes: detecting the concentration of the target gas 700 in the target space 600, such as Figure 4 When the detected concentration of the target gas 700 is greater than a first predetermined concentration, light of a predetermined wavelength is projected toward the photocatalyst 30.

[0132] Specifically, the detection can be achieved through a VOCs sensor, which can be based on a semiconductor principle or an electrochemical principle. The sensor reading value is compared with a first predetermined concentration (a preset judgment threshold). If it exceeds the preset threshold, light of a predetermined wavelength is turned on to irradiate the photocatalytic material.

[0133] In some embodiments, the gas purification method further includes: detecting the concentration of the target gas 700 in the target space 600; when the detected concentration of the target gas 700 is within a predetermined range, projecting light of a predetermined wavelength onto the photocatalyst 30, and introducing oxygen and / or ozone into the target space 600.

[0134] Specifically, when the sensor reading is within a predetermined range, light of a predetermined wavelength is turned on to irradiate the photocatalytic material, and at the same time, oxygen and / or ozone are introduced into the target space 600. The strong oxidizing ozone can promote the oxidation and decomposition of the intermediate small molecular byproducts produced by the initial photocatalytic reaction, and finally completely react to generate harmless water and carbon dioxide and other substances. The introduction of oxygen maintains an oxygen-rich environment in the target space 600 to improve the purification reaction efficiency and purification effect.

[0135] In some embodiments, the gas purification method further includes: detecting the concentration of the target gas 700 in the target space 600; when the detected concentration of the target gas 700 is less than a second predetermined concentration, stopping projecting light of a predetermined wavelength, and stopping introducing and / or generating ozone of a predetermined concentration.

[0136] Specifically, according to the comparison between the sensor reading value and the second predetermined concentration (preset judgment threshold), if it is less than the preset threshold, the light of the predetermined wavelength is turned off to irradiate the photocatalytic material, and the introduction of ozone is stopped.

[0137] In some embodiments, the gas purification method further comprises: collecting or removing the gas after the purification process. Specifically, the purified product can be collected or removed by the exhaust gas treatment device.

[0138] This application embodiment provides a 3D printing system, see Figure 1 , Figure 4 and Figure 5 The 3D printing system includes a 3D printing device 200 and a gas purification device 100. The gas purification device 100 is arranged in a target space 600 associated with the printing material of the 3D printing device 200. The gas purification device 100 can purify the target gas 700 in the target space 600. Further, the gas purification device 100 includes a photocatalyst unit, which includes a photocatalyst 30, a light source assembly 40 and an ozone supply device 50, wherein: the photocatalyst 30 is used to excite and generate oxidizing ions under light conditions to decompose pollutants, the light source assembly 40 is configured to project light of a predetermined wavelength to the photocatalyst 30 to excite the reaction activity of the photocatalyst 30 and perform a catalytic reaction; the ozone supply device 50 is configured to introduce ozone into the target space 600 or generate ozone in the target space 600.

[0139] The gas purification device 100 of the embodiment of the present application is based on the principle of photocatalytic oxidation. It uses the photocatalyst 30 to undergo a chemical oxidation reaction with harmful substances such as VOCs inside and around the 3D printing device 200, thereby decomposing and oxidizing them to obtain harmless substances such as water and carbon dioxide. At the same time, in order to meet the higher purification rate requirements for VOCs harmful gases in the 3D printing scenario, this solution proposes to actively inject ozone into the target space 600 to increase the oxidation of the decomposition products of VOCs gas, so as to meet the higher purification effect required in the 3D printing field and significantly reduce the concentration of harmful gases such as VOCs.

[0140] The gas purification device 100 includes one or more photocatalyst units, a light source assembly 40, and an ozone supply device 50. The gas purification device 100 based on the photocatalytic principle solves the air pollution problem generated during the 3D printing process and improves the safety of the 3D printing device 200.

[0141] In the exemplary embodiment, the photocatalyst 30 exists in the form of an attached layer, and the photocatalyst 30 is a layered structure. The shape and size of the photocatalyst 30 can be various, such as rectangular, circular, irregular polygonal, etc. The component area can be varied according to the lighting requirements and structural design. In other embodiments, the photocatalyst 30 can also exist in other forms, such as loose particles, or cluster structures, etc.

[0142] In some embodiments, the photocatalyst unit also includes a carrier for supporting the photocatalyst 30, and the photocatalyst 30 is arranged on the carrier, wherein the carrier can also be called a catalyst substrate. The photocatalyst 30 is usually coated or attached to a certain substrate or carrier to form a coating or film with catalytic activity. As an example, the carrier can be glass, ceramic, metal, plastic, etc.

[0143] In some optional embodiments, the carrier is a porous structure. The carrier includes but is not limited to honeycomb briquette aluminum filter, alumina porous ceramics, polymer porous foam, etc. The photocatalyst 30 can be attached to these carriers in the form of small molecules. The photocatalyst 30 increases the specific surface area irradiated by light in a mesh or porous manner, thereby further increasing the efficiency of the purification reaction.

[0144] In some embodiments, the gas purification device includes a shell 10, the shell 10 has a gas passage 13 connected to the target space 600, the shell 10 is provided with an air inlet 11 for air flow into the gas passage 13 and an air outlet 12 for air flow out of the gas passage 13, and the photocatalyst 30 is arranged in the gas passage 13. The shell 10 can not only support the photocatalyst 30, but also protect the photocatalyst 30, so that the working state of the photocatalyst 30 is stable.

[0145] Understandably, if Figure 2 As shown, the photocatalyst 30 is located on the flow path of the airflow. After the external airflow flows into the gas passage 13 from the air inlet 11 , it flows through the photocatalyst 30 and then flows out of the gas passage 13 through the air outlet 12 .

[0146] The periphery of the photocatalyst unit can be connected to the inner wall of the gas passage 13 by bonding, snap connection, magnetic adsorption, etc., and the shape of the photocatalyst unit can be adapted to the shape of the cross section of the gas passage 13, so that the contact area between the periphery of the photocatalyst unit and the inner wall of the gas passage 13 is increased, which can not only ensure the stability of the connection of the photocatalyst unit, but also increase the contact area between the photocatalyst 30 and the airflow, thereby improving the purification efficiency. In some examples, the photocatalyst unit is directly carried by the 3D printing device, for example, placed on a part of the 3D printing device.

[0147] Specifically, the photocatalyst unit may be one or more. When the photocatalyst unit is provided as a plurality, the plurality of photocatalyst units are sequentially arranged at intervals along the flow direction of the airflow. In the process of the airflow passing through the gas passage 13, the plurality of photocatalyst units sequentially purify the airflow along the flow direction of the airflow. Of course, the photocatalyst units may also be arranged side by side in the gas passage 13, such as filling the cross section of the gas passage 13 as much as possible, so that the introduced airflow passes through the photocatalyst 30 at the same time, thereby improving the purification effect.

[0148] In addition, the light source assembly 40 can be arranged outside the gas passage 13, and project light of a predetermined wavelength to the photocatalyst 30 through the air inlet 11 or the air outlet 12. Of course, in other possible implementations, the light source assembly 40 can also be arranged in the gas passage 13, and the housing 10 plays a role in supporting the light source assembly 40 and can also protect the light source assembly 40.

[0149] In some embodiments, Figure 2 As shown, the light source assembly 40 is connected to the inner wall of the gas passage 13, and the irradiation surface of the light source assembly 40 faces the photocatalyst 30, so that the photocatalyst 30 can receive the light emitted by the light source assembly 40. Specifically, the light source assembly 40 can be connected to the inner wall of the gas passage 13 by bonding, snap connection, magnetic adsorption, etc.

[0150] Specifically, Figure 4 As shown, the light source assembly 40 includes a light source 41 and a driving circuit 42 for driving the light source 41. The light source 41 includes but is not limited to a mercury lamp, an LED, etc. Mercury lamps are usually driven by high voltage, and have the advantages of high energy and large irradiation area; LEDs are driven by a special step-up / step-down circuit, and the type and quantity of LED lamp beads can be freely designed according to demand, have a long life, and can be designed into different lamp board shapes according to the structure. In addition, the band selection of the light source 41 is also diverse. According to the degree of matching with the selected photocatalyst material, the wavelength of the light source 41 can be freely selected from visible light and ultraviolet light (full band UVA~UVC).

[0151] In some embodiments, the light source 41 is an ultraviolet light source 41. Compared with visible light, ultraviolet light has a shorter wavelength and higher energy. The photocatalyst material excited by ultraviolet light has a higher catalytic activity and can decompose harmful substances more quickly. Generally, the shorter the wavelength of UV light, the higher the energy, and the easier it is to excite the photocatalyst material to produce purification ions.

[0152] The ozone supply device 50 is used to introduce ozone into the target space 600 or generate ozone in the target space 600. It can be understood that the ozone supply device 50 can be arranged in the gas passage 13, specifically, it can be connected to the inner wall of the gas passage 13, in which case the ozone supply device 50 generates ozone in the gas passage 13; the ozone supply device 50 can also be arranged outside the gas passage 13, and the ozone generated by the ozone supply device 50 can be transported to the gas passage 13 through a transport pipeline.

[0153] In a specific embodiment of the present application, taking a titanium dioxide photocatalyst 30 as an example, the photocatalyst 30 is activated under the action of light to produce active substances with strong oxidizing properties, such as OH (hydroxyl radicals) and the like. These active substances can efficiently oxidize organic matter in the exhaust gas. The active substances react with organic matter (VOCs) in the exhaust gas to cause the breakage of the C=C bond (carbon-carbon double bond) and the formation of a new C=O bond (carbon-oxygen double bond). In this process, the organic matter is gradually decomposed into small molecules and can be oxidized by, for example, ozone to ultimately be converted into inorganic matter. In the process of photocatalytic reaction, VOC harmful substances are often not completely decomposed directly into harmless components such as water and carbon dioxide, but at least part of them first open the macromolecular bonds of the macromolecular VOCs to generate new small molecular organic intermediates, which are then further fully decomposed into harmless substances through subsequent redox reactions. If the small molecule intermediate product produced is not completely decomposed during the purification reaction, new pollutants such as irritating odors will be produced. The addition of ozone can solve this problem. The strong oxidizing ability of ozone can further oxidize the intermediate small molecule product produced to obtain harmless substances such as water and carbon dioxide. Although ozone is also one of the intermediate products in the photocatalytic reaction (UV photolysis of oxygen produces a small amount of ozone), the content is relatively low, which is not enough to fully oxidize the intermediate product into water and carbon dioxide. The purification reaction can be further promoted by artificial injection of ozone to achieve a better purification effect. The ozone supply device 50 can be selected from the ozone supply device 50 during discharge to generate ozone by electrolyzing air or oxygen. In certain embodiments, an oxygen supply device can also be used to supply oxygen, which increases the oxygen content in the target space, thereby increasing the ozone content obtained by oxygen under the light reaction, thereby promoting the oxidation reaction.

[0154] The photocatalyst 30 of the embodiment of the present application can quickly stimulate the reaction under light conditions, decompose organic pollutants and VOCs, and the reaction speed is faster than the traditional physical adsorption method, and it also has efficient decomposition ability for bacteria and viruses. The photocatalyst 30 can continue to work under light and will not be consumed during the reaction process, thereby improving the durability of air purification, and the maintenance and replacement frequency of the equipment is low, thereby reducing long-term costs. Moreover, the end products generated by the photocatalytic reaction are usually harmless, such as water, carbon dioxide, nitrogen, etc., which avoids the problem of secondary pollution, and the photocatalyst 30 itself is non-toxic and safe and friendly to the human body and the environment. Therefore, based on the above advantages, the method for efficiently decomposing and purifying harmful gases generated by 3D printing consumables with the principle of photocatalysis proposed in the embodiment of the present application can be applied to 3D printing scenarios of different scales, from small laboratories to large 3D printing farms, with high flexibility; at the same time, the gas purification device 100 of the embodiment of the present application can be used in combination with the existing three-dimensional printing equipment 200 and ventilation system, with high adaptability and integration.

[0155] In some embodiments, see Figure 3 The gas purification device 100 further includes an oxygen supply device 80 for inputting a predetermined concentration of oxygen into the target space 600. It can be understood that the oxygen supply device 80 can be disposed in the gas passage 13, specifically, can be connected to the inner wall of the gas passage 13, in which case the oxygen supply device 80 directly injects ozone into the gas passage 13; the oxygen supply device 80 can also be disposed outside the gas passage 13, and the oxygen generated by the oxygen supply device 80 can be transported to the gas passage 13 through a transport pipeline.

[0156] From the photocatalytic purification principle, it can be known that the photocatalyst material (including but not limited to TiO2 and other modified materials) will not consume its own substances during the purification process but will act as a catalyst, but the O2 and H2O in the reaction space actually participate in the reaction. Therefore, in order to meet the higher purification rate requirements of VOCs harmful gases in the 3D printing scene, the embodiment of the present application proposes to actively inject oxygen through the oxygen supply device 80 to create an oxygen-rich purification environment to improve the efficiency of decomposition and purification.

[0157] In the photocatalytic reaction, oxygen directly participates in the catalytic reaction. Therefore, maintaining the oxygen concentration in the reaction zone can better promote the purification reaction. By controlling the flow rate or concentration of oxygen, an oxygen-rich environment is maintained in the purification reaction area to improve the purification reaction efficiency and purification effect. The oxygen supply device 80 includes but is not limited to a chemical oxygen production device, an electrolytic water oxygen production device, and an adsorption separation oxygen production device. As an example, the adsorption separation oxygen production device includes but is not limited to an air pump plus a molecular sieve structure.

[0158] In some embodiments, see Figure 2 and Figure 3 The gas purification device 100 for 3D printing also includes a ventilation device 90, which is used to accelerate the flow of gas in the target space 600, so that the gas containing high concentrations of VOC harmful components can flow evenly and fully through the surface of the photocatalyst 30.

[0159] Specifically, the ventilation device 90 can be disposed in the gas passage 13, and is used to guide the airflow to flow from the air inlet 11 in the gas passage 13 toward the photocatalyst 30. Specifically, the ventilation device 90 can guide the airflow to flow in the gas passage 13 along the air inlet 11 toward the photocatalyst 30, that is, toward the air outlet 12. The ventilation device 90 can prevent the airflow from diffusing everywhere, so that the airflow including the organic pollutant gas can pass through the photocatalyst 30 as much as possible and be catalytically decomposed, thereby improving the purification efficiency of the gas purification device 100 and improving the output efficiency of the airflow.

[0160] It is understandable that the ventilation device 90 can be disposed between the photocatalyst 30 and the air inlet 11, or between the photocatalyst 30 and the air outlet 12, or at the air inlet 11 or the air outlet 12. The ventilation device 90 can be connected to the inner wall of the gas passage 13 by bonding, snap connection, magnetic adsorption, etc., and a mounting bracket can be provided in the gas passage 13, and the ventilation device 90 can be mounted on the mounting bracket.

[0161] In the embodiment of the present application, the ventilation device 90 includes but is not limited to a fan, a blower and an exhaust system. Among them, the fan can be an axial flow fan, a centrifugal fan or a DC brushless fan. The function of the ventilation device 90 is to promote the gas circulation in the reaction space, so that the gas containing high concentrations of VOC harmful components can flow evenly and fully through the surface of the photocatalyst 30, thereby further improving the purification rate of the reaction area.

[0162] In some embodiments, see Figure 4 The gas purification device 100 also includes a detection unit 60 and a controller 70, wherein: the detection unit 60 is used to detect the concentration of the target gas 700 in the target space 600; the controller 70 is respectively communicated with the light source assembly 40, the ozone supply device 50 and the detection unit 60; the controller 70 is used to control the light source assembly 40 and the ozone supply device 50 according to the concentration of the target gas 700 in the target space 600. Specifically, the controller 70 can control the light intensity of the light source assembly 40 and the amount of ozone generated by the ozone supply device 50 according to the concentration of the target gas 700 in the target space 600 to purify the air.

[0163] In some embodiments, the controller 70 is communicatively connected with the light source assembly 40, the ozone supply device 50, the oxygen supply device 80 and the detection unit 60 respectively; the controller 70 is used to control the light source assembly 40, the ozone supply device 50 and the oxygen supply device 80 according to the pollutant content. Specifically, the controller 70 can control the light intensity of the light source assembly 40, the amount of ozone generated by the ozone supply device 50 and the amount of oxygen generated by the oxygen supply device 80 according to the pollutant content to purify the air.

[0164] In some embodiments, the controller 70 is communicatively connected with the light source assembly 40, the ozone supply device 50, the oxygen supply device 80, the ventilation device 90 and the detection unit 60 respectively; the controller 70 is used to control the light source assembly 40, the ozone supply device 50, the oxygen supply device 80 and the ventilation device 90 according to the concentration of the target gas 700 in the target space 600. Specifically, the controller 70 can control the light intensity of the light source assembly 40, the amount of ozone generated by the ozone supply device 50, the amount of oxygen generated by the oxygen supply device 80 and the output power of the ventilation device 90 according to the concentration of the target gas 700 in the target space 600 to purify the air.

[0165] In order to monitor the VOC content and purification effect in the environment, the detection unit 60 and the controller 70 play a role in feedback closed-loop control. The detection unit 60 includes but is not limited to semiconductor VOCs sensors, electrochemical VOCs sensors, etc. The detection unit 60 can display and record the VOCs components and content in the environment in real time, and the controller 70 can make preset actions based on the data fed back by the detection unit 60, such as starting the entire air purification process.

[0166] It can be found from the chemical reaction formula of the photocatalytic oxidation reaction that in order to promote the sufficiency of the reaction, ozone is injected into the purification reaction area to fully decompose VOCs into harmless substances such as water and carbon dioxide. The VOCs content in the reaction environment is monitored in real time using a pollutant concentration sensor, and the controller 70 automatically makes feedback adjustments to the reaction conditions based on the monitoring results, such as: the intensity of the light source 41, the amount of ozone injected, etc.

[0167] The gas purification device 100 realizes the automatic operation of the air purification process through the detection unit 60 and the controller 70, saving the operator's time and maintenance cost.

[0168] In some embodiments, the detection unit 60 includes an ozone sensor for detecting ozone content. The ozone sensor is used to detect the ozone concentration in the target space 600. The ozone sensor is connected to the controller 70, and the controller 70 regulates the amount of ozone generated by the ozone supply device 50 according to the ozone concentration.

[0169] Since ozone is added to the target space 600 through the ozone supply device 50, and ozone has a clear environmental protection content standard, the ozone sensor can provide real-time feedback on the change of ozone concentration in the environment, so that the controller 70 controls the on and off of the ozone supply device 50 or the amount of ozone injected. The embodiment of the present application uses the ozone sensor feedback to control the ozone concentration in the environment within a safe range.

[0170] In some embodiments, the structure of the 3D printing system is as follows Figure 5 and Figure 6As shown. It can be understood that Figure 6 As shown, the three-dimensional printing device 200 has a closed target space 600, that is, the target space 600 is located inside the three-dimensional printing device 200. Specifically, the three-dimensional printing device 200 includes a molding cabin where printing materials and a printing mechanism are arranged. The target space 600 is the molding space 210 in the molding cabin where printing molding is completed. The printing operation of the three-dimensional printing device 200 is completed in the molding space 210. During the printing process, the volatilization of the printing material itself and the movement and heating of the printing mechanism accelerate the volatilization of the printing material, so that there is a working gas containing a high concentration of VOC organic pollutants in the molding space 210. It can be understood that when the target space 600 is located inside the three-dimensional printing device 200, the target gas 700 of the embodiment of the present application is the working gas in the molding space 210.

[0171] In some embodiments, Figure 6 As shown, the gas purification device 100 is disposed in the molding space 210, and the gas passage 13 is connected to the molding space 210, so the working gas generated in the molding space 210 can directly enter the gas passage 13 for purification. Figure 7 As shown, since the working gas formed in the molding space 210 gradually diffuses upward, the air inlet 11 of the gas purification device 100 can be set downward, and the air outlet 12 of the gas purification device 100 can be set upward, so that enough working gas can enter the gas passage 13 along the air inlet 11, further improving the purification efficiency.

[0172] In some embodiments, the gas purification device 100 is detachably connected to the inner wall of the molding space 210, so that the gas purification device 100 can be easily replaced according to different printing materials. Figure 8 , the side wall of the gas purification device 100 may be provided with a snap-fitting member 510, an adhesive member 520 or a magnetic member 530, so as to be snap-fitted with the inner wall of the molding space 210 through the snap-fitting member 510, bonded with the inner wall of the molding space 210 through the adhesive member 520, or adsorbed and connected with the inner wall of the molding space 210 through the magnetic member 530. Specifically, the snap-fitting member 510 may be a hook, the adhesive member 520 may be a sticker, and the magnetic member 530 may be a magnet. In other possible embodiments, the gas purification device 100 may also be detachably connected to the inner wall of the molding space 210 through a fastener 540, and specifically, the fastener 540 may be a bolt.

[0173] In some embodiments, Figure 4 and Figure 5As shown, the target space 600 accommodates at least one 3D printing device 200, that is, the gas purification device 100 and the 3D printing device 200 are both accommodated in the target space 600, and the gas purification device 100 is arranged outside the molding space 210. The 3D printing system also includes an air guide component 300, which is used to transport the target gas 700 in the target space 600 to the gas purification device 100. It can be understood that the air guide component 300 can not only transport the working gas in the molding space 210 to the gas purification device 100, but also transport the working gas leaking from the molding space 210 to the outside of the 3D printing device 200 to the gas purification device 100.

[0174] The air guide assembly 300 may include a ventilation duct and an air pump, the ventilation duct connects the target space 600 and the air inlet 11, and the air pump drives the target gas 700 in the target space 600 to be transported to the air inlet 11. Specifically, the gas purification device 100 may be arranged at the bottom of the 3D printing device 200, and the air inlet 11 and the air outlet 12 are respectively arranged at the left and right sides of the gas purification device 100. The gas purification device 100 is arranged at the bottom of the 3D printing device 200 to make full use of the space at the bottom of the 3D printing device 200, thereby reducing the lateral size of the 3D printing system.

[0175] In some embodiments, Figure 4 As shown, the 3D printing system further includes an exhaust gas treatment device 400, which is used to collect or remove products obtained by purifying the target gas 700. Specifically, the exhaust gas treatment device 400 can be connected to the air outlet 12, and the exhaust gas treatment device 400 can draw the gas treated by the gas purification device 100 back to the 3D printing device 200 for internal circulation or discharge it to the outside of the 3D printing system.

[0176] In some embodiments, Fig. 9 As shown, an embodiment of the present application provides a 3D printing system, the 3D printing system includes multiple three-dimensional printing devices 910, 920, and a gas purification device 930. The gas purification device 930 is arranged in the space of the 3D printing system and is connected to the target space containing printing materials of the three-dimensional printing devices 910, 920. The gas purification device 930 can purify the target gas in the target space containing printing materials of the three-dimensional printing devices 910, 920. Additionally or alternatively, the gas purification device can purify the target gas in the space of the 3D printing system (i.e., the space containing multiple three-dimensional printing devices).

[0177] In some embodiments, in combination Figures 1 to 11 The purification method of the above 3D printing system comprises:

[0178] The light source assembly 40 and the ozone supply device 50 of the gas purification device 100 are turned on to purify the working gas of the 3D printing device 200.

[0179] In some embodiments, the light source assembly 40 and the ozone supply device 50 of the gas purification device 100 are turned on to purify the working gas of the 3D printing device 200 , which also includes: obtaining the pollutant content of the gas passage 13 of the gas purification device 100 .

[0180] Specifically, the following steps may be included:

[0181] Step S1, turn on the detection unit 60 (such as a VOCs sensor) to detect and read the sensor value:

[0182] After each 3D printing process is completed, for convenience, the material box containing the consumables is usually not thoroughly cleaned. After a period of volatilization, the VOCs content inside the equipment usually exceeds the safety threshold. In order to prevent the operator from inhaling excessive harmful gases and causing physical discomfort when starting a new 3D printing process, it is necessary to test the VOCs content inside the equipment to ensure that the environment before printing meets the environmental standards. This detection can be achieved through a VOCs sensor, which can be based on semiconductor principles or electrochemical principles. The controller 70 (such as a computer) obtains the VOCs content value in the equipment by communicating with the sensor.

[0183] Step S2, comparing the sensor reading value with a preset judgment threshold:

[0184] The value of the VOCs sensor read by the computer is compared with the preset VOCs content alarm threshold, and the next step is performed according to the judgment result. If it is lower than the preset threshold, the 3D printing device 200 enters the 3D printing process; if it exceeds the preset threshold, the 3D printing device 200 gives a prompt and enters the photocatalyst air purification process.

[0185] Step S3, prompt and start the air purification process:

[0186] After the three-dimensional printing device 200 prompts and starts the air purification process, the gas purification device 100 starts working. First, the light source assembly 40 is turned on, and the light source 41 is lit under the drive of the driving circuit 42. The light source 41 here can be visible light or UV light of different bands, depending on the type of light source 41 selected and the degree of matching of the photocatalyst material. Secondly, the form of the light source 41 can be a high-pressure mercury lamp tube, or an LED lamp bead / lamp board or other forms. After the light source 41 is lit, it irradiates the photocatalyst material, and a chemical reaction occurs on the surface of the photocatalyst material to generate negative oxygen ions and hydroxyl radical ions with strong oxidizing properties. These ions undergo redox reactions with VOCs molecules in the environment and eventually decompose them into harmless water, carbon dioxide and other substances. At the same time, the ozone supply device 50 is started, and ozone is generated by the ozone generation module. The strongly oxidizing ozone can promote the oxidative decomposition of the intermediate small molecule byproducts produced by the initial reaction of the photocatalyst, and finally completely react to generate harmless water, carbon dioxide and other substances. As the purification reaction proceeds, the value of the VOCs sensor gradually decreases.

[0187] Step S4, comparing the sensor reading value with a preset judgment threshold:

[0188] The sensor value is compared with the preset alarm threshold again. If it is lower than the preset threshold, the gas purification device 100 can be turned off, and / or the 3D printing device 200 enters the 3D printing process; if it is higher than the preset threshold, step S3 is repeated.

[0189] In some embodiments, the air purification method also includes: obtaining the pollutant content of the air passage of the gas purification device 100 at every preset time interval; if the pollutant content exceeds a preset threshold, controlling the power of the light source assembly 40 to increase and controlling the amount of ozone generated by the ozone supply device 50 to increase; if the pollutant content is lower than the preset threshold, turning off the light source assembly 40 and the ozone supply device 50.

[0190] Specifically, the following steps may be included:

[0191] Step S1, turning on the detection unit 60 (e.g., VOCs sensor) to detect and read the sensor value;

[0192] Step S2, comparing the sensor reading value with a preset judgment threshold;

[0193] Step S3, prompting and starting the air purification process;

[0194] Step S4: Comparing the sensor reading value with the preset judgment threshold: The sensor value is compared with the preset alarm threshold again. If it is lower than the preset threshold, the gas purification device 100 can be turned off, and / or the three-dimensional printing device 200 enters the 3D printing process; if it is higher than the preset threshold, the power of the light source assembly 40 is controlled to increase and the amount of ozone generated by the ozone supply device 50 is controlled to increase.

[0195] In some embodiments, when the gas purification device 100 also includes the oxygen supply device 80, the air purification method further includes: controlling the opening and closing of the oxygen supply device 80 according to the pollutant content, and controlling the oxygen concentration generated by the oxygen supply device 80 when the oxygen supply device 80 is turned on.

[0196] Specifically, the following steps may be included:

[0197] Step S1, turning on the detection unit 60 (e.g., VOCs sensor) to detect and read the sensor value;

[0198] Step S2, comparing the sensor reading value with a preset judgment threshold;

[0199] Step S3, prompt and start the air purification process:

[0200] After the air purification process is started, the gas purification device 100 starts working. First, the light source 41 is lit under the drive of the driving circuit 42. At the same time, the oxygen supply device 80 and the ozone supply device 50 inside the equipment are turned on. Oxygen can be generated by an air pump plus a molecular sieve structure. By filling a certain concentration of oxygen into the reaction area to create an oxygen-rich environment, it is beneficial to purify the photocatalyst catalytic reaction. Ozone is generated by the ozone supply device 50. The strongly oxidizing ozone can promote the oxidation of the intermediate small molecular byproducts produced by the initial hydrolysis reaction of the photocatalyst, and finally completely react to generate harmless water and carbon dioxide and other substances. As the purification reaction proceeds, the value of the TVOC sensor gradually decreases.

[0201] Step S4, based on the comparison between the sensor reading value and the preset judgment threshold: the sensor value is compared with the preset alarm threshold again. If it is lower than the preset threshold, the gas purification device 100 can be turned off, and / or the three-dimensional printing device 200 enters the 3D printing process; if it is higher than the preset threshold, the power of the light source assembly 40 is controlled to increase, the amount of ozone generated by the ozone supply device 50 is controlled to increase, and the oxygen concentration generated by the oxygen supply device 80 is controlled to increase.

[0202] In some embodiments, when the gas purification device 100 also includes a ventilation device 90, the air purification method also includes: controlling the opening and closing of the ventilation device 90 according to the pollutant content, and controlling the wind speed generated by the ventilation device 90 when the ventilation device 90 is turned on.

[0203] Specifically, the following steps may be included:

[0204] Step S1, turning on the detection unit 60 (e.g., VOCs sensor) to detect and read the sensor value;

[0205] Step S2, comparing the sensor reading value with a preset judgment threshold;

[0206] Step S3, prompt and start the air purification process: After the three-dimensional printing device 200 prompts and starts the air purification process, the gas purification device 100 starts working. First, the light source 41 is lit under the drive of the driving circuit 42. At the same time, the ventilation device 90 (such as a fan or blower) inside the gas purification device 100 starts to start, and the gas in the reaction space is flowed under the action of the fan / blower, increasing the contact area and rate between the VOCs molecules and the photocatalyst material. At the same time, the oxygen and ozone generators inside the gas purification device 100 are turned on. As the purification reaction proceeds, the value of the VOCs sensor gradually decreases.

[0207] Step S4, based on the comparison between the sensor reading value and the preset judgment threshold: the sensor value is compared with the preset alarm threshold again. If it is lower than the preset threshold, the three-dimensional printing device 200 enters the 3D printing process; if it is higher than the preset threshold, the power of the light source assembly 40 is controlled to increase, the amount of ozone generated by the ozone supply device 50 is controlled to increase, the oxygen concentration generated by the oxygen supply device 80 is controlled to increase, and the wind speed of the ventilation device 90 is controlled to increase.

[0208] In some embodiments, when the gas purification device 100 also includes an ozone sensor, the method also includes: obtaining the ozone concentration of the air outlet 12 of the gas purification device 100 at preset time intervals, controlling the opening and closing of the ozone supply device 50 according to the ozone concentration, and controlling the amount of ozone generated by the ozone supply device 50 when the ozone supply device 50 is turned on.

[0209] In some embodiments, the air purification method further includes: detecting the pollutant content in the gas passage 13 in real time; and controlling the gas purification device 100 to shut down when the pollutant content is lower than a preset threshold.

[0210] In some embodiments, the air purification method further includes: performing pollutant content detection after each 3D printing and / or during the 3D printing process, and determining whether to start the gas purification device 100 based on the detection results.

[0211] Specifically, the following steps may be included:

[0212] Step S1, turning on the detection unit 60 (e.g., VOCs sensor) to detect and read the sensor value;

[0213] Step S2, comparing the sensor reading value with a preset judgment threshold;

[0214] Step S3, prompting and starting the air purification process;

[0215] Step S4, comparing the sensor reading value with the preset judgment threshold: the sensor value is compared with the preset alarm threshold again. If it is lower than the preset threshold, the 3D printing device 200 enters the 3D printing process; if it is higher than the preset threshold, step S3 is repeated.

[0216] Step S5, starting the 3D printing process;

[0217] Step S6, the 3D printing process ends;

[0218] Step S7, after completing the 3D printing process, the operator usually needs to open the closed printing door on the printing device and take out the 3D printed parts for subsequent post-processing operations such as cleaning and curing. During the 3D printing process, the liquid photosensitive resin in the material tray will be stirred due to the lifting movement of the printing platform. At the same time, some three-dimensional printing devices 200 will have functions such as resin heating, which will accelerate the volatilization of VOCs components in the liquid resin material, resulting in an increase in the VOCs content in the three-dimensional printing device 200. If the operator opens the equipment door at this time, he may inhale excessive harmful components and cause physical discomfort. Therefore, it is necessary to perform another VOCs content detection and judgment.

[0219] Step S8, prompting and starting the air purification process, as above;

[0220] Step S9, compare the sensor reading value with the preset judgment threshold: compare the sensor value with the preset alarm threshold again. If it is lower than the preset threshold, enter S10 to start the exhaust gas treatment and emission process; if it is higher than the preset threshold, repeat step S8.

[0221] In some embodiments, the air purification method further includes: the treated gas is drawn back into the 3D printing device 200 for circulation through the exhaust gas treatment device 400 , or discharged to the outside of the 3D printing device 200 .

[0222] The following describes the invention in conjunction with specific embodiments.

[0223] Embodiment 1:

[0224] See also Figure 1The embodiment of the present application provides a gas purification device 100, which is applied to a three-dimensional printing device 200. The gas purification device 100 has a gas passage 13, and the gas passage 13 is provided with an air inlet 11 and an air outlet 12. The gas purification device 100 also includes a photocatalyst 30 (TiO2 photocatalyst filter element), a light source assembly 40 (ultraviolet lamp) and an ozone supply device 50.

[0225] The air purification method using the above-mentioned gas purification device 100 in the three-dimensional printing equipment 200 includes the following steps: turning on the ultraviolet lamp, setting the ultraviolet wavelength to 254nm and the power to 30W; at the same time, turning on the ozone supply device 50, generating an ozone amount of 50mg / h to purify the air.

[0226] Embodiment 2:

[0227] See also Figure 2 The embodiment of the present application provides a gas purification device 100, which is applied to a three-dimensional printing device 200. The gas purification device 100 has a gas passage 13, and the gas passage 13 is provided with an air inlet 11 and an air outlet 12. The gas purification device 100 also includes a photocatalyst 30 (TiO2 photocatalyst filter element), a light source assembly 40 (ultraviolet lamp), an ozone supply device 50 and an oxygen supply device 80.

[0228] The air purification method using the above-mentioned gas purification device 100 in the three-dimensional printing equipment 200 includes the following steps: turning on the ultraviolet lamp, setting the ultraviolet wavelength to 254nm, and the power to 30W; at the same time, turning on the ozone supply device 50, and generating an ozone amount of 50mg / h; at the same time, turning on the oxygen supply device 80, and generating an oxygen amount of 1L / min, so that the oxygen content in the gas passage 13 is maintained at 30% to 50%, and air purification is performed.

[0229] Comparative Example 1:

[0230] The comparative example of the present application provides a gas purification device 100, which is applied to a three-dimensional printing device 200. The gas purification device 100 has a gas passage 13, and the gas passage 13 is provided with an air inlet 11 and an air outlet 12. The gas purification device 100 also includes a photocatalyst 30 (TiO2 photocatalyst filter element) and a light source assembly 40 (ultraviolet lamp).

[0231] The air purification method using the gas purification device 100 in the three-dimensional printing device 200 includes the following steps: turning on the ultraviolet lamp, setting the ultraviolet wavelength to 254nm and the power to 30W, and performing air purification.

[0232] Comparative Example 2:

[0233] The comparative example of the present application provides a gas purification device 100, which is applied to a three-dimensional printing device 200. The gas purification device 100 has a gas passage 13, and the gas passage 13 is provided with an air inlet 11 and an air outlet 12. The gas purification device 100 also includes a photocatalyst 30 (TiO2 photocatalyst filter element), a light source assembly 40 (ultraviolet lamp) and an oxygen supply device 80.

[0234] The air purification method using the above-mentioned gas purification device 100 in the three-dimensional printing equipment 200 includes the following steps: turning on the ultraviolet lamp, setting the ultraviolet wavelength to 254nm, and the power to 30W; at the same time, turning on the oxygen supply device 80, and generating an oxygen amount of 1L / min, so that the oxygen content in the gas passage 13 is maintained at 30% to 50%, and air purification is performed.

[0235] Comparative Example 3:

[0236] The gas purification device includes a photocatalyst (TiO2 photocatalyst filter element) and an ozone supply device, and ozone is introduced into the target space at 50 mg / h. There is no ultraviolet radiation and no additional oxygen is introduced.

[0237] Comparative Example 4:

[0238] The gas purification device includes a photocatalyst (TiO2 photocatalyst filter element) and an oxygen supply device, and oxygen is introduced into the target space at 1L / min. There is no ultraviolet irradiation and no additional ozone is introduced.

[0239] Comparative Example 5:

[0240] The gas purification device includes a photocatalyst (TiO2 photocatalyst filter element) and an oxygen supply device, and oxygen is introduced into the target space at 1L / min. There is no ultraviolet irradiation and no additional ozone is introduced.

[0241] After 8 minutes, the concentration of related organic matter (including organic matter directly from the printing material and small molecular products obtained by its decomposition) in the space is detected by using, for example, a TVOC detector. The results are shown in Table 1 below.

[0242] Table 1

[0243]

[0244] From the test results in Table 1, it can be seen that Example 1 actively injects ozone but does not introduce additional oxygen (oxygen exists in the air). The data results show that the VOCs content is significantly reduced by more than 75%, indicating that the odor of the resin can be basically eliminated by additional ozone. Example 2 injects oxygen and ozone at the same time. The data results show that the VOCs content is further reduced and the odor caused by organic matter can be basically eliminated.

[0245] Since there is no ozone injection in Comparative Example 1 and Comparative Example 2, both have an increase in VOCs values, because the products of VOCs decomposition under light conditions are detected by the sensor, and at least a part of the products also emit odor, resulting in an unsatisfactory purification effect. Comparative Example 2 is a case where oxygen is injected alone without ozone injection, and the VOCs content still increases, but it is lower than that of Comparative Example 1. This is because 254nm UV light can decompose oxygen in the air to produce ozone, and the additional oxygen input causes the amount of ozone generated to increase, so that part of the products of VOCs decomposition are oxidized by the increased ozone, so that the detected VOCs content is lower than that of Comparative Example 1. However, the amount of ozone generated by this reaction is not enough to completely react with all the products after decomposition. Injecting or preparing additional ozone is helpful in eliminating the influence of resin odor.

[0246] Comparative Example 3 relies only on ozone to oxidize VOCs, but it is difficult to oxidize all VOCs. Only part of the VOCs are oxidized, and the excess ozone also emits an odor. Comparative Example 4 only injects additional oxygen. The test results show that in the absence of ultraviolet light, VOCs are basically not eliminated or converted. Comparative Example 4 injects additional oxygen and ozone at the same time, but does not apply ultraviolet light. The test results show that under normal lighting conditions (indoor light), TiO2 can promote the decomposition of VOCs in an oxygen-rich environment, and the injected ozone can react with the small molecule products after decomposition, but the overall purification effect of this scheme is not as good as that under ultraviolet conditions.

[0247] The application also conducted the following test: for a 60L target space, a 30W mercury lamp provided ultraviolet light with a wavelength of 254nm, a ceramic filter containing TiO2 was provided, ozone was input into the target space at a flow rate of 50mg / H, and oxygen was input into the target space at a flow rate of 1L / min. The initial VOCs content in the target space detected by the TVOC sensor was 0.8mg / m 3 When the input oxygen concentration is 30%, the VOCs content detected by the TVOC sensor after 15 minutes is basically 0.001mg / m 3 When the input oxygen concentration is 35%, the VOCs content detected by the TVOC sensor after 8 minutes is basically 0.001mg / m 3 When the input oxygen concentration is 40%, the VOCs content detected by the TVOC sensor after 5 minutes is basically 0.001mg / m 3 .

[0248] Fig.10A purification flow chart is shown. The target gas (VOCs) 1010 from the printing material of the three-dimensional printing device is passed to the photocatalyst 1020 (e.g., TiO2), and the light source 1030 (e.g., ultraviolet light) applies light to excite the photocatalyst 1020. The photocatalyst 1020 undergoes electronic transition and reacts with oxygen in the space, thereby promoting the decomposition of the target gas 1010 into small molecule products 1050. The aforementioned oxygen can be oxygen in the air (concentration of about 21%), or it can be oxygen 1040 supplied by an oxygen supply device, which increases the oxygen concentration in the target space, thereby promoting the decomposition of the target gas. Those skilled in the art can understand that the hydrolysis reaction of VOCs under light and catalyst involves the participation of O2 and H2O. The "input O2" described in this application has indicated that there is a corresponding H2O to react (e.g., H2O in the air has met the requirements of the hydrolysis reaction). The small molecule product 1050 is oxidized by ozone 1060 to generate a final product 1070 (e.g., CO2 and H2O). Ozone 1060 can be produced by an ozone generator and introduced into the target space (e.g., applied to a photocatalyst), or alternatively obtained by photolysis or electrolysis of oxygen in the target space 1080. The H2O in the final product 1070 can be used to act in the hydrolysis reaction of VOCs.

[0249] By using the solution provided by the present application, the three-dimensional printing device 200 can be used in more user application scenarios, such as schools, hospitals, offices, personal homes and other places.

[0250] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A gas purification method for three-dimensional printing, characterized in that: include: Providing a target space, in which a printing material for three-dimensional printing is arranged, so that the target space includes a target gas originating from the printing material; Arranging a photocatalyst in the target space; Projecting light of a predetermined wavelength toward the photocatalyst to excite the photocatalyst; Inputting oxygen into the target space to increase the concentration of oxygen in the target space; and Ozone is supplied to the target space and / or generated in the target space.

2. The gas purification method according to claim 1, characterized in that: The target space: configured to accommodate at least one three-dimensional printing device; or Limited by a single 3D printing device.

3. The gas purification method according to claim 2, characterized in that: The three-dimensional printing device includes any one of a DLP printing device, an LCD printing device, an FDM printing device, an SLA printing device, and an inkjet three-dimensional printing device.

4. The gas purification method according to claim 1, characterized in that: The photocatalyst includes at least one of titanium dioxide, zinc oxide, tungsten trioxide and modified titanium dioxide.

5. The gas purification method according to claim 4, characterized in that: The modified titanium dioxide includes at least one of non-metal-doped titanium dioxide, metal-doped titanium dioxide, precious metal-deposited titanium dioxide, and heterostructured titanium dioxide.

6. The gas purification method according to claim 1, characterized in that: The light of predetermined wavelength includes visible light and / or ultraviolet light.

7. The gas purification method according to claim 6, characterized in that: emitting visible light using a first light source; and / or A second light source is used to emit ultraviolet light, independent of the first light source.

8. The gas purification method according to claim 1, characterized in that: The light of predetermined wavelength includes at least one wavelength selected from the following ranges: 190nm-280nm, 281nm-320nm, 321nm-400nm.

9. The gas purification method according to claim 8, characterized in that: The light of predetermined wavelength includes at least one wavelength selected from the following ranges: 240nm-260nm, 310nm-320nm, 340nm-360nm.

10. The gas purification method according to claim 1, characterized in that: Inputting oxygen into the target space includes: continuously or intermittently inputting oxygen into the target space at a predetermined flow rate to promote decomposition of organic compounds in the target gas.

11. The gas purification method according to claim 1, characterized in that: Inputting oxygen into the target space includes: using an oxygen supply device to output oxygen of a predetermined concentration to the target space, wherein the predetermined concentration is 25% to 100%.

12. The gas purification method according to claim 1, characterized in that: The oxygen input into the target space includes: inputting oxygen toward the photocatalyst so that 0.5m 3 The average oxygen concentration in the space is 28% to 70%.

13. The gas purification method according to claim 1, characterized in that: The oxygen input into the target space includes: inputting oxygen into the target space so that a 5m 3 The average oxygen concentration in the space is 30% to 50%.

14. The gas purification method according to claim 1, characterized in that: The inputting ozone into the target space and / or generating ozone in the target space comprises: decomposing oxygen in the target space using the light of the predetermined wavelength to obtain ozone; and / or, Using electric current to decompose oxygen in the target space to obtain ozone; and / or, Ozone is fed into the target space independently of the target space.

15. The gas purification method according to claim 1, characterized in that: The concentration of oxygen and the concentration of ozone input into the target space are configured so that the concentration of the target gas and the concentration of ozone in at least a portion of the target space are both 0 to 0.050 mg / m 3 , preferably 0 to 0.005 mg / m 3 .

16. The gas purification method according to claim 1, characterized in that: Also includes: A ventilation device is used to accelerate the flow of gas in the target space.

17. The gas purification method according to claim 1, characterized in that: Also includes: detecting the concentration of the target gas in the target space; When the detected concentration of the target gas is greater than a first predetermined concentration, light of a predetermined wavelength is projected toward the photocatalyst.

18. The gas purification method according to claim 1, characterized in that: Also includes: detecting a concentration of a target gas associated with a printing material in the target space; When the detected concentration of the target gas is less than a second predetermined concentration, the projection of the light of the predetermined wavelength is stopped, and the input and / or generation of ozone is stopped.

19. The gas purification method according to claim 1, characterized in that: Also includes: The gas treated by the purification and / or the products obtained by the purification of the gas are collected or removed.

20. A 3D printing system, characterized in that: The invention comprises a three-dimensional printing device and a gas purification device, wherein the gas purification device is arranged in a target space associated with a printing material of the three-dimensional printing device, and the gas purification device comprises: A photocatalyst unit, comprising a photocatalyst; a light source assembly configured to project light of a predetermined wavelength toward the photocatalyst; an oxygen supply device configured to input oxygen into the target space to increase the concentration of oxygen in the target space; and The ozone supply device is configured to input ozone into the target space or generate ozone in the target space.

21. The 3D printing system according to claim 20, characterized in that: It also includes a ventilation device, which is used to accelerate the flow of gas in the target space; optionally, the oxygen supply device includes a molecular sieve.

22. The 3D printing system according to claim 20, characterized in that: The gas purification device includes a shell, which defines a gas passage connected to the target space. The shell is provided with an air inlet for airflow into the gas passage and an air outlet for the airflow in the gas passage to flow out. The photocatalyst is arranged in the gas passage.

23. The 3D printing system according to claim 20, characterized in that: The photocatalyst comprises at least one of titanium dioxide, zinc oxide, tungsten trioxide, and modified titanium dioxide; And / or, the photocatalyst unit further comprises a carrier for carrying the photocatalyst; And / or, the light source assembly is an ultraviolet light source.

24. The 3D printing system according to claim 23, characterized in that: The modified titanium dioxide comprises at least one of the following: non-metal-doped titanium dioxide, metal-doped titanium dioxide, precious metal-deposited titanium dioxide, and heterostructured titanium dioxide.

25. The 3D printing system according to claim 20, characterized in that: It also includes a detection unit and a controller, wherein the detection unit is used to detect the concentration of a target gas associated with the printing material in the target space, wherein the controller is communicatively connected with the light source assembly, the ozone supply device, the oxygen supply device and the detection unit respectively; and the controller is used to control the light source assembly, the ozone supply device and the oxygen supply device according to the concentration of the target gas.

26. The 3D printing system according to claim 25, characterized in that: The detection unit includes an ozone sensor for detecting ozone content.

27. The 3D printing system according to claim 20, characterized in that: The three-dimensional printing device has a closed target space; or The target space accommodates at least one of the three-dimensional printing devices.

28. The 3D printing system according to claim 20, characterized in that: The 3D printing system further includes an exhaust gas treatment device, which is used to collect or remove products obtained by purifying the target gas and / or gases after purification.

29. The 3D printing system according to claim 20, characterized in that: The gas purification device is bonded to a three-dimensional printing device; or The gas purification device is snap-connected to the three-dimensional printing device; or The gas purification device is magnetically connected to the three-dimensional printing device; or The gas purification device is carried by a three-dimensional printing device.

30. A gas purification method for three-dimensional printing, characterized in that: include: Providing a target space, in which printing materials for three-dimensional printing are arranged; Arranging a photocatalyst in the target space; Projecting light of a predetermined wavelength toward the photocatalyst to excite the photocatalyst; and Ozone of a predetermined concentration is introduced into the target space and / or generated in the target space.

31. The gas purification method according to claim 30, characterized in that: The step of inputting ozone of a predetermined concentration into the target space and / or generating ozone of a predetermined concentration in the target space comprises: Using light to decompose oxygen in the target space to obtain ozone; or Using electric current to decompose oxygen in the target space to obtain ozone; or An ozone supply device is used to output ozone to the target space.

32. The gas purification method according to claim 30, characterized in that: Also includes: Oxygen of a predetermined concentration is input into the target space to increase the oxygen concentration in the target space.

33. The gas purification method according to claim 32, characterized in that: Inputting a predetermined concentration of oxygen into the target space includes: inputting oxygen into the target space so that 1 m 3 or 3m 3 The average oxygen concentration in the space is 30% to 45%.

34. The gas purification method according to claim 32, characterized in that: Inputting oxygen of a predetermined concentration into the target space includes: using an oxygen supply device to output oxygen of a predetermined concentration to the target space, wherein the predetermined concentration is 30% to 90%.

35. The gas purification method according to claim 32, characterized in that: The concentration of oxygen and the concentration of ozone input into the target space are configured so that the concentration of the target gas and the concentration of ozone in at least a portion of the target space are both 0 to 0.060 mg / m 3 , preferably 0 to 0.010 mg / m 3 .

36. A 3D printing system, characterized in that: The invention comprises a three-dimensional printing device and a gas purification device, wherein the gas purification device is arranged in a target space associated with a printing material of the three-dimensional printing device, and the gas purification device comprises: A photocatalyst unit, comprising a photocatalyst; a light source assembly configured to project light of a predetermined wavelength toward the photocatalyst; and The ozone supply device is configured to introduce ozone into the target space or generate ozone in the target space.

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