92 results about "Microwave plasma torch" patented technology

The present invention relates to a synthesis method of carbon nanotubes, and more particularly to an apparatus for a mass synthesis of carbon nanotubes in gas phase using an atmospheric-pressure microwave plasma torch. The method and apparatus is described for the continuous production of carbon nanotubes by making use of a microwave plasma torch operated at a frequency of 2.45 GHz, by introducing a transition metal catalyst precursor and a carbon containing gas into the microwave plasma torch to produce atomized catalyst metal and to decompose the carbon containing gas, by passing the resulting gaseous mixtures through a furnace, and by quenching rapidly and collecting the products so formed at the exit of the furnace. The resultant products are the carbon nanotubes.

Disclosed herein is a method to produce multiphase composite materials directly from solution precursor droplets by a fast pyrolysis process using a microwave plasma embodiment containing a microwave generating source, a dielectric plasma torch, and a droplet maker. Here, using homogenous solution precursors, droplets are generated with a narrow size distribution, and are injected and introduced into the microwave plasma torch with generally uniform thermal path. The generally uniform thermal path in the torch is achieved by axial injection of droplets into an axisymmetric hot zone with laminar flows. Upon exposing to high temperature within the plasma with controlled residence time, the droplets are pyrolyzed and converted into particles by quenching with a controlled rate of the exhaust gas in a gas chamber. The particles generated have generally uniform sizes and uniform thermal history, and can be used for a variety of applications.

The invention relates to a double-cavity excitation enhanced microwave plasma torch generation device, and belongs to the technical field of microwave plasma. The device comprises a microwave magnetron, a circulator, a directional coupler, a microwave plasma coupling waveguide, a cylindrical waveguide, an igniter and a discharge tube. After the microwave magnetron, the circulator and the directional coupler are sequentially connected in series, the directional coupler is connected with the microwave plasma coupling waveguide. The cylindrical waveguide chamber is additionally arranged in the axial direction of the discharge tube perpendicular to a compression rectangular waveguide; a thermal resistance waveguide in the microwave plasma coupling waveguide effectively isolates the influence of thermal release of plasma discharge on a whole system; the igniter makes the whole system operated by a single person to complete a series of processes of ignition, excitation and maintenance, and the ignition success rate is close to 100% under the condition that the no-load output of a microwave source is low. Plasma torch afterglow with a larger volume action area can be obtained by increasing the maximum power of a plasma torch, so that the device can operate stably and reliably for a long time, and can be used in various relevant fields such as combustion assistance, nano material synthesis, waste gas treatment and high-temperature-resistant material surface modification.

The invention provides a waveguide direct-feed-type microwave plasma torch device which comprises a waveguide portion, a tuning and auxiliary portion and a coaxial torch tube portion. The waveguide portion comprises a gradual-changing-type waveguide and a narrow-edge compression waveguide. The coaxial torch tube portion comprises an outer tube, a middle tube, an inner tube, a regulating stud and a coaxial centering washer. The tuning and auxiliary portion comprises a waveguide short-circuit sliding end, a torch tube reflection tuning end and a torch tube upper portion regulating end. The waveguide short-circuit sliding end comprises a waveguide short-circuit plate and a sliding rod. The torch tube reflection tuning end comprises the regulating stud and a reflection plate. The gradual-changing-type waveguide and the narrow-edge compression waveguide are directly fed into the metal coaxial torch tube, a formed plasma has a central channel so that a sample can be conveniently led into the plasma, and meanwhile bearing capacity for the sample is intensified. The device eliminates a coaxial cable, a coupling ring and the like, improves coupling efficiency, and expands the use power of the torch tube. The device can be used as an ionization source of an atomizer and an ionization source of an atom mass spectrum or used for decomposition and treatment of harmful chemicals and rubbish.

The present invention relates to an apparatus for generating flames and more particularly to the microwave plasma burner for generation of high-temperature plasma flame by injecting gaseous, liquid or solid-powder hydrocarbon-fuels into plasma generated by microwaves. The invention provides a compact and portable apparatus for generating plasma flame. The apparatus includes a magnetron, an electrical power supplier, a waveguide system, a microwave power monitering system, stub tuners, a discharge tube, a gas supply system, a plasma ignitor and a fuel supply system. The method and apparatus is described for generation of a large volume of high-temperature plasma by injecting gaseous, liquid or solid-powder hydrocarbon-fuels into the microwave plasma torch to decompose the hydrogen and carbon containing fuels, and to mix the resultant gaseous hydrogen and carbon compounds with air or oxygen gas, instantaneously generating a large volume of high-temperature flames.

A large power microwave plasma torch includes a tuned coaxial resonator, a rectangular waveguide with a wavequide / coaxial converting device to be structure blocked up and down by a door-knob block a door-knob structure locked up and down by a door-knob block and a medium line and con closely with top bottom surfaces of the rectangular wavequide, the said resonator is composed of an top and bottom cavities coaxial with the converter and placed at either side of the waveguide and the converter, one end of the inner conductor is plug in the low cavity, the other end passes through the medium single line, door-knob block and the up cavity, a resonator sort circuit piston is set along the axial line between inner and outer conductors, one end of the waveguide is set with a micro wave source and a waveguid a microwave source and a waveguide shout circuit piston at the other.

A method for processing feed material to produce dense and spheroidal products is described. The feed material is comprised of powder particles from the spray-drying technique or solution precursor droplets from ceramic or metallic materials. The feed material is processed using plasma generated from a microwave. The microwave plasma torch employed is capable of generating laminar flow during processing which allows for the production of spheroidal particles with a homogenous materials distribution. This results in products having improved thermal properties, improved corrosion and wear resistance and a higher tolerance to interface stresses.

The invention discloses a microwave plasma ignition device, which comprises a microwave resonance cavity, a quartz glass tube plasma generating area, a tangential air supply device and a coal dust flow blowing-in device. The coal dust flow blowing-in device axially blows coal dust flow into the microwave plasma generating area in a quartz glass tube; when the input microwave power exceeds a critical value, the microwave plasma generating area generates initial ionization under the excitation of micro coal dust in the coal dust flow, and the initial ionization is transited to the whole quartz glass tube through avalanche effect so as to form a microwave plasma torch. Meanwhile, the coal dust flow is ignited to form a coal dust microwave plasma torch and is blown out from the upper end of the quartz glass tube along the axial direction of the quartz glass tube. The coal dust and the microwave plasma are mutually acted so as to raise the temperature of the output torch of the ignition device, increase the ignition, combustion support and combustion stabilization capabilities of the microwave plasma ignition device and meanwhile overcome the defects that the microwave plasma torch is excited by coaxial inner conductors in the microwave plasma generating area and the high-temperature plasma torch melts the coaxial inner conductors due to long time.

The invention provides a microwave plasma torch device which comprises a cavity part, a microwave coupling part and a tuning part. The cavity part comprises an inner tube, a middle tube and an outer tube, wherein the inner tube, the middle tube and the outer tube are successively coaxially arranged from the inside out. One end of the cavity part is open. The tuning part is arranged on the other end to adjust the field strength of the open end. A microwave coupling opening is arranged in the side wall of the outer tube. The microwave coupling part and the cavity part are in microwave coupling through the microwave coupling opening. A first microwave resonant cavity is formed between the outer tube and the middle tube. A porous pad which is used for coaxially fixing the inner tube and the middle tube is arranged between the inner tube and the middle tube. The first microwave resonant cavity couples microwave into a space between the inner tube and the middle tube through the open end of the cavity part to form a second microwave resonant cavity. The upper surface of the porous pad is the reflective surface of the second microwave resonant cavity. The microwave plasma torch device provided by the invention has the advantages of wide application power range and excellent plasma gas stability, and further avoids a series of problems caused by superposition of high-strength electric field pyrogenicity and a plasma heat source.

The invention is related to an apparatus made of microwave plasma burner for a large-volume elimination of toxic airborne chemical and biological warfare agents. The apparatus can purify the interior air of large volume in an isolated space such as buildings, public transportation systems, and military vehicles contaminated with chemical and biological warfare agents. The apparatus consists of a microwave plasma torch connected in series to a fuel injector and a reaction chamber for elimination and burnout of toxic airborne warfare agents in large quantities. Hydrocarbon fuel in gaseous or liquid state injected into the microwave plasma torch evaporates instantaneously, generating a large volume of plasma flame in the reaction chamber where the oxidation mechanism eliminates the chemical and biological warfare agents that pass through the reaction chamber. The apparatus can also purify air contaminated with volatile organic compounds and eliminate soot from diesel engines.

The invention provides a self-tuning microwave plasma torch and a self-tuning device of the self-tuning microwave plasma torch. The microwave plasma torch (4) comprises a coupled antenna (5) and a regulating part (6). The self-tuning device comprises a microwave source, a control module (2) and a transmission device (3). The microwave source is connected with the coupled antenna (5). The regulating part (6) is connected with the transmission device (3). The transmission device (3) is connected with the control module (2). The control module (2) is connected with the microwave source. The microwave source generates a microwave electromagnetic field to provide microwave energy for the microwave plasma torch (4) and acquires feedback information of the microwave plasma torch (4) from the coupled antenna (5) at the same time; the microwave source extracts a reflection power value from the feedback information and feeds back the reflection power value to the control module (2); the control module sends a control signal to the transmission device (3) according to the reflection power value and a preset parameter relation curve, and the transmission device (3) drives the regulating part (6) to move.

A low-temperature plasma chemical reactor for producing ethyne by cracking natural gas and its process are disclosed. The reactor consists of microwave plasma torch and DC plasma exciting mechanism. The external conductor of the microwave plasma torch is of hollow structure, of which outlet forms a nozzle, the DC plasma exciting mechanism consists of external conductor, conductive pipe corresponding to the external conductor nozzle, the cavity of the conductive pipe as reacting chamber , the external conductor as cathode, the conductive pipe as anode, with the conductive pipe connected with DC electric source by choking structure. The process is carried out by: microwave plasma entering into DC plasma exciting mechanism; 2) microwave plasma forming normal DC plasma under the action of the DC electric source, and natural gas cracking to obtain ethyne. It achieves long life and high efficiency.

A coaxial microwave plasma torch, comprising, an outside conductor (1) formed in a cylindrical shape, a cylindrical electric discharge tube (3) fixedly inserted into an axial hole (2) formed in the outside conductor on one end face (4) side, and a coaxial cable (6) having one end fitted to the other end face of the outside conductor. An antenna (9) electrically connected to an inside conductor (8) is fitted to the one end of the coaxial cable and extended into the electric discharge tube through a through-hole (11) axially passed through between the other end face (5) of the outside conductor and the bottom ice of the axial hole. The outside conductor (7) of the coaxial cable is electrically connected to the outside conductor, and a gas inlet pipeline (13) supplying a gas into the electric discharge tube is fitted in the outside conductor.

A method for processing feed material to produce dense and spheroidal products is described. The feed material is comprised of powder particles from the spray-drying technique or solution precursor droplets from ceramic or metallic materials. The feed material is processed using plasma generated from a microwave. The microwave plasma torch employed is capable of generating laminar flow during processing which allows for the production of spheroidal particles with a homogenous materials distribution. This results in products having improved thermal properties, improved corrosion and wear resistance and a higher tolerance to interface stresses.

There is provided a microwave plasma torch system comprising: a plasma generator; a microwave generator; and at least one plasma source gas injector, wherein the microwave generator includes a waveguide, wherein the plasma generator includes a discharge tube, wherein the discharge tube passes through a waveguide in a perpendicular to the waveguide, wherein the waveguide has a width na, where n is an integer equal to or larger than 2, wherein a is defined as a width of a waveguide having a dominant mode for propagating a microwave, wherein the discharge tube is positioned relative to the waveguide such that a diameter center of the tube encounters a longitudinal null line of an electric field distribution, wherein the discharge tube is further positioned relative to the waveguide such that a diameter center of the tube encounters a transverse null line of an electric field distribution, wherein the transverse null line is perpendicular to the longitudinal null line.

The invention provides a microwave plasma torch ionization source and an ionization mass spectrometry analysis method. The ionization source comprises a microwave plasma torch tube and a sampling system which are horizontally and coaxially placed, wherein an open end is arranged at the head of the microwave plasma torch tube and is toward an ion transport pipe opening of a mass spectrometry scanner; the sampling system is connected with the tail part of the microwave plasma torch tube; and a spray sampling device is adopted by the sampling system. Mass spectrometry analysis is carried out by cooperation of the microwave plasma torch ionization source and the mass spectrometry scanner. A traditional pneumatic atomizing desolvation device is replaced with the spray sampling device, so that the structure of an ionization source device is simple, the ionization efficiency is high, the sample consumption during ionization analysis is low, the analysis speed is high and the analysis cost is significantly reduced for high-cost or rare samples.

The invention discloses a method for treating waste by adopting a microwave plasma torch. The method comprises the following steps: pretreatment of waste, namely preparing solid waste, liquid waste and gaseous waste, and crushing the solid waste by virtue of a crushing device; and pyrolysis, namely generating a plasma torch by carrying out ionization on gas by utilizing a microwave plasma generation device, and carrying out the pyrolysis on the pre-treated waste by virtue of the plasma torch, wherein organic matters in the waste are pyrolyzed into micromolecular substances such as C, H2, CO, and CH4, and inorganic matters in the waste are molten at the high temperature to form a matter in a glass state. According to the method, the waste is pyrolyzed by virtue of the plasma torch generated by the microwave plasma generation device, the waste is pyrolyzed into the micromolecular substances, such as carbon oxide, carbon powder, methane, and hydrogen, and the matter in the glass state, no harmful matter is generated in the treatment process, the secondary pollution for the environment is avoided, the treatment procedure is simple, and the efficiency is relatively high.

The invention discloses a gas-phase reaction buffer chamber based on an atmospheric pressure microwave plasma torch, and belongs to the field of plasma technology and environmental chemistry application. The gas-phase reaction buffer chamber comprises a gas injection part, a buffer chamber, a gas-pressure meter and an exhaust pump; the buffer chamber is arranged above the gas injection part, and the top of the buffer chamber is connected with the gas-pressure meter and the exhaust pump; the gas injection part comprises a rectangular waveguide, a movable metal baffle, a buffer chamber flange and a discharge tube, working gas is introduced into the discharge tube to form a vortex gas flow field, and the working gas in the discharge tube is induced by a microwave electric field to be ionizedto form microwave plasma discharge. Certain working air pressure is kept in the buffer chamber, so that the plasma torch is kept in a stable discharge state. According to the invention, the plasma density and the electron temperature in the interaction area of the plasma and the gas can be increased, the chemical reaction rate of the plasma gas-phase reaction can be further improved, and the gas introduced into the discharge tube can completely and fully participate in the plasma chemical reaction.

The invention provides a solid sample direct introduction device of a microwave plasma torch spectrometer. The solid sample direct introduction device mainly includes pulsed laser system, an imaging positioning system, a sample processing system, a position regulating system and an air path switching system. Through the adoption of the solid sample direct introduction device disclosed by the invention, the direct sampling analysis of solid samples comprising biological samples, metallic materials and the like can be realized, besides, the device is suitable for sampling regular sample surfaces and irregular sample surfaces, direct laser ablation sampling can atomize all the elements, and the device can be used for full elementary analysis of the microwave plasma torch spectrometer. The device can be applied to many existing fields of metallurgy, medical inspection, life science, agriculture, food safety detection, forestry, environmental monitoring, biological identification, medicolegal expertise and the like. The device disclosed by the invention is reasonable in design, and can be used for direct sample introduction for the solid samples, the pretreatment steps of the samples are decreased, requirements for the material state of the samples are lower, and the device satisfies user demands.

The microwave plasma torch full spectrometer is a kind of spectral instrument for simultaneous multispectral detection in atomic emission spectrum analysis. The structure includes built-in water cooled microwave power source system, microwave plasma torch system, optical path system comprise concave reflector and optical fiber, spectroscopic detection system with spectroscopic detection module comprising flattening grating and ultraviolet enhanced array detector, and computer system. The present invention has small volume, small stable microwave power, conveniently altered spectral range, simultaneous detection of multiple elements, and other advantages.

The invention discloses a technological method for preparing LTCC amorphous glass ceramic powder with a microwave plasma torch. The technological method comprises the following steps: mixing raw materials of glass, ball milling, drying, and granulating into particles with diameters of 1-3mm, and sintering into ceramic balls at 650-850DEG C; and rapidly fusing the hot ceramic balls into glass droplets through the microwave plasma torch with the temperature of 3000-5000DEG C, falling into deionized water, chilling to obtain an amorphous glass ceramic material with the particle size of 15-500mum, carrying out wet ball milling, and drying to a product the LTCC amorphous glass ceramic powder. According to the invention, methods for fusing glass with platinum and ceramic crucibles in traditional technologies are abandoned, and the glass droplets are in a suspending state in the process of fusing with the microwave plasma torch and do not contact with any vessels, so the technological methodof the invention which has the advantages of guarantee of the glass purity, convenient operation, uniform glass chilling, obvious effect better than the traditional technologies, good product consistency, and good economy is in favor of the large scale production.

The invention provides an automatically ignited microwave plasma torch device. The automatically ignited microwave plasma torch device consists of an outer tube, an intermediate tube, an inner tube, a space ring, a microwave coupling interface, an outer tube microwave opening, a coupling rod, a coupling ring, a reflection end face, and a regulating piston. The microwave plasma torch is formed by a section of the opened metal coaxial resonant cavity of three coaxial tubes, and the microwave is used for forming the plasma torch at the opening end. The automatically ignited microwave plasma torch device is capable of changing the ignition mode of the microwave plasma torch, and enabling the torch tube to realize the autoignition without an additional device through regulating the relative position of the inner tube of the torch tube, so the usability of the microwave plasma torch device is greatly enhanced, the effect of a high-pressure ignition needle to the design of the microwave shielding structure can be eliminated, the device structure is simplified, and the reliability and the stability of the device are enhanced. The microwave plasma torch is used for the plasma source for the analysis of the atomic emission spectroscopy, and also used for the plasma source for the technical field of the chemistry and measurement.

Arc plasma torch generated by a torch module installed on the bottom wall in the narrow section of a tapered S-band rectangular cavity, is used to seed microwave discharge where the microwave electric field is maximum. This tapered cavity is designed to support TE103 mode. With seeding, only low Q cavity and moderate microwave power (time average power of 700 W) are needed. The microwave-enhanced discharge increases the size, cycle energy, and duty cycle of the seeding arc-torch plasma considerably. This torch can be run stably without introducing gas flow or run just using airflow. Adding airflow can increase not only the size of the torch plasma but also its cycle energy, which may reach a plateau of about 12 J / per cycle for the airflow rate exceeding 0.393 l / s. This microwave plasma torch may have a radius of about 1.25 cm or more, a height of about 5 cm, and a peak electron density exceeding 5*10<13>cm<-3>. This torch may produce an abundance of reactive atomic oxygen, and therefore may be used in applications for rapidly destroying a broad spectrum of chemical and biological warfare (CBW) agents.

The invention provides a lampblack purification device for microwave plasma torches. Lampblack and air are introduced into a purification tank for mixing, a stable high-temperature plasma region is generated by a microwave plasma torch array in the purification tank, high-energy impact is performed on harmful organic molecules in lampblack, original molecular bonds of the lampblack are opened, small molecular substances excited by high energy are converted into clean final products such as carbon dioxide, water and the like in an oxygen-enriched environment, and the purpose of lampblack purification is achieved. According to the device, power distribution of the microwave plasma torch array can be adjusted automatically according to gas flow and concentration of the lampblack, the treating effect and the efficiency of energy use are improved, the air supplementing quantity is adjusted according to a remaining oxygen detection value of a discharging pipe after purification, sufficient oxidation of organic pollutants in the lampblack is guaranteed, and the purifying treatment rate is guaranteed.

The invention belongs to the technical field of high purity poly-silicon preparation, which particularly relates to a method for preparing high-purity silicon powder through a microwave plasma torch technology. The method adopts a microwave plasma torch to separate mixed gas of uniformed mixed high-purity raw gas and diluent gas, high-purity silicon powder is obtained after the separation of gas and powder, ingot casting or monocrystal pulling is performed in a vacuum melting furnace, so that high-purity silicon ingot is obtained, residual gas is conducted to tail gas treatment, separated raw gas is reused, and obtained chlorine gas or hydrogen chloride gas is prepared into side products. The method can be performed in the atmosphere, reduces the time and energy consumption during vacuum melting, is energy-saving and efficient, has less process steps and reduces the level of pollution from exogenous impurity, the purity of obtained silicon powder is high, produced tail gas can be reused and prepared into side products, the energy waste is reduced, and the environment is protected.