CN110127603A - The method of high-throughput reaction of low temperature plasma device and decomposing hydrogen sulfide - Google Patents

Abstract

The invention relates to the field of plasma chemistry, and discloses a high-throughput low-temperature plasma reactor and a method for decomposing hydrogen sulfide, comprising: an inner cylinder (1) containing at least two parallel reaction tubes (14); The outer outer cylinder (2) of the inner cylinder (1); the central high-voltage electrode (3), the central high-voltage electrode (3) is respectively arranged in each reaction tube (14); the ground electrode (4) forms the ground electrode ( The material in 4) is a solid conductive material; the barrier medium, the barrier medium forms at least part of the side wall of the reaction tube or the barrier medium is arranged around the inner side wall of each of the reaction tubes (14). The aforementioned high-flux low-temperature plasma reactor provided by the present invention can be used for plasma decomposition of hydrogen sulfide, and the reactor can generate uniform and efficient dielectric barrier discharge, thereby directly decomposing hydrogen sulfide to generate hydrogen and sulfur.

Description

High-throughput low-temperature plasma reactor and method for decomposing hydrogen sulfide

technical field

The invention relates to the field of plasma chemistry, in particular to a high-throughput low-temperature plasma reactor and a method for decomposing hydrogen sulfide.

Background technique

Hydrogen sulfide (H ₂ S) is a highly toxic and foul-smelling acid gas, which not only causes corrosion of metals and other materials, but also endangers human health and pollutes the environment. At present, large and medium-sized refineries in China adopt the traditional Claus method to treat tail gas containing H ₂ S and recover sulfur. The method recovers only the sulfur in hydrogen sulfide, but converts the valuable hydrogen into water. From the perspective of comprehensive utilization of resources, hydrogen resources have not been effectively utilized in the traditional hydrogen sulfide recovery process. Therefore, the decomposition of hydrogen sulfide into sulfur and hydrogen has gradually become a technical field that researchers at home and abroad pay close attention to.

At present, hydrogen sulfide decomposition methods mainly include: pyrolysis method, electrochemical method, photocatalytic method and low temperature plasma method. Among the aforementioned methods, the high-temperature pyrolysis method is relatively mature in industrial technology, but the thermal decomposition of hydrogen sulfide strongly depends on the reaction temperature and is limited by thermodynamic equilibrium. Only 20%. In addition, high temperature conditions have higher requirements on reactor materials, which will also increase operating costs. In addition, due to the low thermal decomposition conversion rate of hydrogen sulfide, a large amount of hydrogen sulfide gas needs to be separated from the tail gas and circulated in the system, which also reduces the efficiency of the device and increases energy consumption, which brings difficulties to its large-scale industrial application . Although the use of membrane technology can effectively separate products to break the equilibrium limit and increase the conversion rate of hydrogen sulfide, the thermal decomposition temperature often exceeds the limit heat-resistant temperature of the membrane, which damages the structure of the membrane material. The electrochemical method has disadvantages such as many operation steps, serious equipment corrosion, poor reaction stability and low efficiency. The photocatalytic decomposition of hydrogen sulfide mainly draws on the research of photocatalytic water splitting, and the research focuses on the development of high-efficiency semiconductor photocatalysts. Using solar energy to decompose hydrogen sulfide has the advantages of low energy consumption, mild reaction conditions, and simple operation, and is a relatively economical method. However, this method has problems such as small processing capacity, low catalytic efficiency and easy deactivation of the catalyst.

Compared with other decomposition methods, the low-temperature plasma method has the advantages of simple operation, small device volume, high energy efficiency, etc., and the reactions involved in it are highly controllable, and can be flexibly processed in the case of small processing volume and difficulty in centralized processing. application. In addition, due to its high energy density and shortened reaction time, it can effectively decompose hydrogen sulfide at a lower temperature, and is suitable for occasions with different scales, scattered layouts, and variable production conditions. Moreover, while recovering sulfur, the low-temperature plasma method recovers hydrogen resources, which can realize the utilization of hydrogen sulfide resources.

At present, researchers at home and abroad have conducted extensive research on the technology of low-temperature plasma decomposition of hydrogen sulfide. The discharge forms used mainly include glow discharge, corona discharge, sliding arc discharge, microwave plasma, radio frequency plasma and dielectric barrier discharge. .

Document "International journal of hydrogen energy", 2012, 37: 1335-1347. Decompose hydrogen sulfide by shrinking normal glow discharge method. Under the conditions of pressure 0.02Mpa and temperature 2000-4000K, the minimum energy consumption of hydrogen sulfide decomposition is 2.35eV/ _H2S . However, the reaction temperature is high, the pressure is low, and the harsh conditions are not easy to realize.

The document "International journal of hydrogen energy", 2012, 37: 10010-10019 uses microwave plasma to decompose hydrogen sulfide. Under the conditions of atmospheric pressure and temperature 2400K, hydrogen sulfide can be completely decomposed, but the decomposed hydrogen and sulfur will be rapidly decomposed at high temperature. Compounding regenerates hydrogen sulfide, and there is no corresponding quenching measure at present.

Document "Chemical Engineering Science", 2009, 64(23): 4826-4834. Using pulsed corona discharge to carry out the research on H ₂ S decomposition to produce hydrogen and sulfur. The reactor adopts a line-tube structure. The effects of pulse forming capacitance, discharge voltage and pulse frequency on H ₂ S conversion rate and decomposition energy efficiency were investigated. The results show that under the condition of constant power, low pulse forming capacitance, low discharge voltage and high pulse frequency are beneficial to obtain high H ₂ S decomposition energy efficiency; in addition, compared with Ar and N ₂ as balance gas, Ar-N ₂ When the gas is used as the balance gas, a higher H ₂ S conversion rate can be obtained. When the volume fraction of Ar/N ₂ /H ₂ S is 46%/46%/8%, the discharge power is 60W, and the pulse forming capacitance is 720pF, the obtained H The lowest decomposition energy consumption of ₂ S is 4.9eV/H ₂ S, but the conversion rate of H ₂ S is only about 30%. In addition, the flow rate of this reaction system is only 1.18×10 ^-4 SCMs ^-1 , and the reaction effect of low flow rate, low concentration and low conversion rate has no practical significance in industrial production.

The literature "Journal of applied physics", 1998, 84(3): 1215-1221 used sliding arc discharge to study the decomposition reaction of H ₂ S. The method was to dilute H ₂ S with air to a concentration of 0-100ppm. The effects of gas flow rate, reaction chamber size and frequency on the H ₂ S decomposition reaction were investigated under the condition that the total gas flow rate was 0-100L/min. The experimental results show that low gas flow rate, small disc spacing and low frequency are beneficial to obtain a higher H ₂ S conversion rate. Under optimized discharge conditions, the H ₂ S conversion rate can reach 75-80%, but the H ₂ S decomposition energy The consumption is as high as 500eV/H ₂ S, and the reaction effect of low concentration and high energy consumption also has no industrial application prospect.

Dielectric barrier discharge can usually be generated under atmospheric pressure, and the discharge temperature is relatively low. In addition, due to the existence of the medium, the growth of the discharge current is limited, thereby avoiding the complete breakdown of the gas to form sparks or arcs, which is conducive to the generation of large-volume and stable plasma, and has a good industrial application prospect.

The literature "Plasma chemistry and plasma processing", 1992, 12(3): 275-285 used an improved ozone generator to investigate the discharge characteristics of H ₂ S in the range of 130-560°C, and studied the reaction temperature, H ₂ S The influence of feed concentration, injection power and addition of H ₂ , Ar, N ₂ etc. on H ₂ S conversion rate and energy efficiency, the experiment found that the addition of Ar can promote the decomposition of H ₂ S, at a total flow rate of 50-100mL/min, H When the ₂ S concentration is 20-100%, the conversion rate is 0.5-12%, and the minimum hydrogen production energy consumption is about 0.75mol/kWh (50eV/H ₂ ), however, this process still has low conversion rate and high energy consumption Shortcomings.

CN102408095A uses dielectric barrier discharge and photocatalyst to decompose hydrogen sulfide synergistically. The method is to fill the plasma region with a solid catalyst with photocatalytic activity. However, this method has the disadvantage that sulfur generated by hydrogen sulfide decomposition will be deposited under the catalyst bed.

Document "International Journal of Energy Research", 2013, 37(11): 1280-1286. Al ₂ O ₃ , MoO _x /Al ₂ O ₃ , CoOx/Al ₂ O ₃ and NiO/Al ₂ O ₃ catalysts are filled in Discharge area, H ₂ S decomposition was studied using dielectric barrier discharge and catalyst. The reaction results show that the MoOx/Al ₂ O ₃ and CoOx/Al ₂ O ₃ catalysts have better effects; when the MoOx/Al ₂ O ₃ catalyst is filled, the total flow rate of H ₂ S/Ar is 150mL/min, the concentration of H ₂ S is 5 When the volume %, the injection specific energy SIE is 0.92kJ/L, and the catalyst filling length is 10% of the bed, the highest conversion rate of H ₂ S obtained is about 48%. However, the concentration of hydrogen sulfide in this reaction process is low, and the sulfur produced by decomposition is deposited inside the reactor. As time goes on, the activity of the catalyst decreases and the discharge stability decreases, resulting in a gradual decrease in the conversion rate of hydrogen sulfide.

CN103204466A discloses a temperature-controlled hydrogen sulfide decomposition device and method, the device is characterized in that the central electrode is a metal, the ground electrode is a temperature-controllable circulating liquid, through the temperature control of the liquid ground electrode, the hydrogen sulfide decomposition process can be continuous steady progress. In addition, CN103204467A discloses a device and method for continuously and stably decomposing hydrogen sulfide to produce hydrogen. The feature of this prior art is that the center electrode is a metal and the ground electrode is a temperature-controllable circulating liquid, and the temperature is controlled by the liquid ground electrode. , the raw material intake direction is circumferential intake, and passes through the discharge area reversely along the axial direction in a spiral mode, so that the generated sulfur is centrifugally separated in time. However, in the methods disclosed by CN103204466A and CN103204467A, in order to ensure that hydrogen sulfide is decomposed as fully as possible, it is necessary to control the flow rate of hydrogen sulfide so that its residence time in the inner cylinder of the reactor is longer and to control the size of the inner cylinder so that the unit volume of hydrogen sulfide in the inner cylinder is The electric energy obtained by the gas is more, and, because the current prior art cannot provide a power source with greater power, the method disclosed in CN103204466A and CN103204467A is adopted even if the residence time of hydrogen sulfide is controlled longer and the size of the inner cylinder is controlled so that the inner cylinder The more electric energy obtained by the unit volume of gas in the cylinder can only make the highest conversion rate of hydrogen sulfide reach about 20%, and when the highest conversion rate of hydrogen sulfide reaches about 20%, the energy consumption of hydrogen sulfide decomposition reaction is quite high. Not suitable for large industrial applications. Furthermore, the methods disclosed in CN103204466A and CN103204467A also have the defect that there are very few types of liquid grounding electrodes available, and the salt solutions disclosed therein can only maintain the temperature of the reactor below 100°C, and below 100°C, the simple substance Sulfur is generally solid and can easily cause blockage of the reactor.

Contents of the invention

One of the objectives of the present invention is to provide a new high-efficiency A flux low-temperature plasma reactor and a method for decomposing hydrogen sulfide using the reactor.

The second object of the present invention is to provide a high-throughput low-temperature plasma reactor with high hydrogen sulfide decomposition conversion rate and low decomposition energy consumption.

In order to achieve the above object, in a first aspect, the present invention provides a high-throughput low-temperature plasma reactor, the reactor has a jacketed tubular structure, and the reactor includes:

An inner cylinder, the inner cylinder is respectively provided with a reactor inlet and a product outlet, and the inner cylinder contains at least two reaction tubes arranged side by side, and the top and bottom of each of the reaction tubes communicate with each other correspondingly, so that by the The raw materials entering the reactor inlet can enter each of the reaction tubes respectively, and the products produced in each of the reaction tubes can be drawn out from the product outlet;

An outer cylinder, the outer cylinder is nested outside the inner cylinder, and the outer cylinder is respectively provided with a heat transfer medium inlet and a heat transfer medium outlet, and the heat transfer medium introduced by the heat transfer medium inlet can be distributed in the inner cylinder Between each of the reaction tubes of the barrel, and the heat transfer medium is drawn out from the heat transfer medium outlet;

a central high-voltage electrode, the central high-voltage electrode is respectively arranged in each of the reaction tubes of the inner cylinder;

A ground electrode, the material forming the ground electrode is a solid conductive material, and the ground electrode forms at least part of the side wall of each of the reaction tubes or the ground electrode is respectively arranged around the outer side wall of each of the reaction tubes;

a barrier medium forming at least part of the side wall of each of the reaction tubes so that at least part of the barrier medium surrounds the central high voltage electrode, or the barrier medium is disposed around the inner side wall of each of the reaction tubes;

In each of the reaction tubes, the barrier medium is positioned such that a discharge area between the central high voltage electrode and the ground electrode is separated by the barrier medium,

In each of the reaction tubes, the proportional relationship between the distance L ₁ between the outer wall of the central high-voltage electrode and the inner wall of the barrier medium and the thickness D ₁ of the barrier medium is: L ₁ : D ₁ = (0.05～100):1.

In a second aspect, the present invention provides a method for decomposing hydrogen sulfide, which is implemented in the high-throughput low-temperature plasma reactor described in the first aspect of the present invention, the method comprising: under dielectric barrier discharge conditions, containing The raw material gas of hydrogen sulfide is introduced from the reactor inlet into each reaction tube of the inner cylinder of the high-throughput low-temperature plasma reactor to carry out the decomposition reaction of hydrogen sulfide, and the stream obtained after the decomposition is drawn out from the product outlet, and, through Continuously introducing the heat-conducting medium from the heat-conducting medium inlet into the outer cylinder of the high-flux low-temperature plasma reactor and drawing the heat-conducting medium out from the heat-conducting medium outlet to maintain the temperature required by the high-flux low-temperature plasma reactor, The dielectric barrier discharge is formed by a ground electrode, a barrier medium and a central high voltage electrode.

The aforementioned high-flux low-temperature plasma reactor provided by the present invention can be used for plasma decomposition of hydrogen sulfide, and the reactor can generate uniform and efficient dielectric barrier discharge, thereby directly decomposing hydrogen sulfide to generate hydrogen and sulfur.

The aforementioned high-flux low-temperature plasma reactor of the present invention can realize high-conversion decomposition of hydrogen sulfide under high-flux conditions, and the decomposition energy consumption is low.

Description of drawings

Fig. 1 is a structural schematic diagram of a preferred embodiment of the high-throughput low-temperature plasma reactor provided by the present invention.

Explanation of reference signs

1. Inner cylinder 2. Outer cylinder

11. Reactor inlet 21. Heat transfer medium inlet

12. Gas product outlet 22. Heat transfer medium outlet

13. Liquid product export

14. Reaction tube

3. Central high voltage electrode

4. Grounding electrode

5. Ground wire

Detailed ways

Neither the endpoints nor any values of the ranges disclosed herein are limited to such precise ranges or values, and these ranges or values are understood to include values approaching these ranges or values. For numerical ranges, between the endpoints of each range, between the endpoints of each range and individual point values, and between individual point values can be combined with each other to obtain one or more new numerical ranges, these values Ranges should be considered as specifically disclosed herein.

As mentioned above, the present invention provides a high-throughput low-temperature plasma reactor, the reactor has a jacketed sleeve structure, and the reactor includes:

An inner cylinder, the inner cylinder is respectively provided with a reactor inlet and a product outlet, and the inner cylinder contains at least two reaction tubes arranged side by side, and the top and bottom of each of the reaction tubes communicate with each other correspondingly, so that by the The raw materials entering the reactor inlet can enter each of the reaction tubes respectively, and the products produced in each of the reaction tubes can be drawn out from the product outlet;

An outer cylinder, the outer cylinder is nested outside the inner cylinder, and the outer cylinder is respectively provided with a heat transfer medium inlet and a heat transfer medium outlet, and the heat transfer medium introduced by the heat transfer medium inlet can be distributed in the inner cylinder Between each of the reaction tubes of the barrel, and the heat transfer medium is drawn out from the heat transfer medium outlet;

a central high-voltage electrode, the central high-voltage electrode is respectively arranged in each of the reaction tubes of the inner cylinder;

A ground electrode, the material forming the ground electrode is a solid conductive material, and the ground electrode forms at least part of the side wall of each of the reaction tubes or the ground electrode is respectively arranged around the outer side wall of each of the reaction tubes;

a barrier medium forming at least part of the side wall of each of the reaction tubes so that at least part of the barrier medium surrounds the central high voltage electrode, or the barrier medium is disposed around the inner side wall of each of the reaction tubes;

In each of the reaction tubes, the barrier medium is positioned such that a discharge area between the central high voltage electrode and the ground electrode is separated by the barrier medium,

In each of the reaction tubes, the proportional relationship between the distance L ₁ between the outer wall of the central high-voltage electrode and the inner wall of the barrier medium and the thickness D ₁ of the barrier medium is: L ₁ : D ₁ = (0.05～100):1.

The difference between "side wall" and "outer side wall" and "inner side wall" in the present invention is: "outer side wall" and "inner side wall" respectively represent the outer surface and inner surface of the "side wall".

In the present invention, the structure formed by the respective reaction tubes whose tops and bottoms communicate with each other is called an inner cylinder.

Each of the reaction tubes of the present invention is respectively provided with a central high-voltage electrode. Preferably, the central high-voltage electrode is provided at the axis of each reaction tube, so as to facilitate the uniform discharge of the reactor of the present invention. The central high-voltage electrodes in each reaction tube at each axis position can be connected to the power supply respectively; the central high-voltage electrodes in each reaction tube at each axis position can also be connected in parallel in the reactor inner cylinder, and then Connect each central high-voltage electrode connected in parallel to a power supply.

According to a preferred specific embodiment, the barrier medium forms at least part of the side wall of each of the reaction tubes so that at least part of the barrier medium surrounds the central high-voltage electrode, and the ground electrodes are respectively arranged around each of the on the outer wall of the reaction tube.

More preferably, all side walls of each of the reaction tubes are formed by the barrier medium.

In the present invention, two specific situations are provided for the arrangement of the barrier medium. The first one is that the barrier medium forms at least part of the side wall of each of the reaction tubes so that at least part of the barrier medium surrounds the central high pressure electrode, and when the setting form of the barrier medium is the first case, the ground electrode is set on the outer wall of the reaction tube; the second is that the barrier medium is arranged around each of the reaction tubes and the ground electrode forms at least part of a side wall of each of the reaction tubes.

The jacketed sleeve structure design of the present invention can make the heat-conducting medium circulate in the shell layer, maintain the entire reactor within a certain temperature range while ensuring the discharge intensity, and make the generated sulfur flow out of the reactor in liquid form , can effectively avoid the solidification of sulfur generated by the decomposition of hydrogen sulfide, and can achieve a high conversion rate while making the decomposition process continuous and stable to achieve long-term operation.

Preferably, in each of the reaction tubes, the proportional relationship between the distance L1 between the outer wall of the central high _- voltage electrode and the inner wall of the barrier medium and the thickness D1 _of the barrier medium is _: L1 : D ₁ =(0.1-30):1. The inventors _of the present invention have found in research that by controlling the relationship between L and D within the aforementioned scope _of the present invention, especially when within the aforementioned preferred range, the reactor of the present invention can be more obviously compared with the prior art Improve the conversion rate of hydrogen sulfide and reduce the energy consumption of decomposition.

According to a preferred specific implementation manner, the central high-voltage electrodes in each of the reaction tubes are connected in parallel with each other.

Preferably, the material forming the barrier medium is an electrical insulating material, more preferably the material forming the barrier medium is at least one selected from glass, ceramics, enamel, polytetrafluoroethylene, mica and high-voltage electrical insulating metal. The glass can be quartz glass or hard glass; the material forming the barrier medium can also be other metal and non-metal composite materials with high voltage electrical insulation design. The ceramics may be alumina ceramics.

Preferably, the reactor further includes a grounding wire, the grounding wire is arranged on the outer wall of the outer cylinder, and one end thereof is connected to the grounding electrode in each of the reaction tubes.

Preferably, the reactor inlet is arranged at the upper part of the inner cylinder, and the product outlet is arranged at the lower part and/or bottom of the inner cylinder.

According to a preferred specific embodiment, the product outlet includes a gas product outlet and a liquid product outlet, and the gas product outlet is arranged at the lower part of the inner cylinder, and the liquid product outlet is arranged at the bottom of the inner cylinder bottom.

According to a preferred specific implementation manner, the size of each of the reaction tubes is the same. The same size means that the size and shape of each of the reaction tubes are completely the same. The arrangement of the reaction tubes in the present invention is not particularly limited, and the arrangement cross-section may be a regular triangle, a regular hexagon, a circle, and the like.

In the present invention, in each of the reaction tubes, the ratio of the inner diameter of the reaction tube to the pore diameter of the product outlet may be (0.1˜100):1.

In the present invention, the ratio of the pore diameter of the reactor inlet to the pore diameter of the product outlet may be (0.1˜120):1.

In each of the reaction tubes, the ratio between the length of the reaction tube and the inner diameter of the reaction tube of the present invention may be (0.5˜500):1.

Preferably, the gas product outlet is arranged below all the discharge areas, and the gas product outlet is located between the height H1 _of the bottom of the inner cylinder and the length _L2 of the discharge area. The proportional relationship is: H ₁ : L ₂ =1: (0.05-25000); preferably H ₁ : L ₂ =1: (0.1-10000); more preferably H ₁ : L ₂ =1: (0.5-1000 ).

Preferably, the heat-conducting medium inlet and the heat-conducting medium outlet are respectively arranged at the lower part and the upper part of the outer cylinder.

The reactor inlet of the present invention can be arranged so that the raw material gas entering the inner cylinder is parallel to the inner diameter of the inner cylinder or at a certain angle, for example, it can be arranged tangentially.

The inner diameters in the present invention all represent diameters.

Preferably, the material forming the ground electrode is selected from graphite tube, metal tube, metal foil or metal mesh. The solid ground electrode of the present invention generates larger micro-discharge current under the condition of constant injection power, and is more conducive to the bond breaking and decomposition reaction of hydrogen sulfide. The metal tube and metal foil in the material forming the ground electrode may include simple metal tube, simple metal foil, alloy metal tube, and alloy metal foil. The inventors of the present invention have found that when a solid conductive material is used as the ground electrode to surround the outer wall of the reaction tube or form at least part of the side wall of the reaction tube, the high-flux low-temperature plasma reaction provided by the present invention can be used. When the hydrogen sulfide decomposition reaction is carried out in the reactor, the conversion rate of hydrogen sulfide is more significantly improved.

Preferably, the ground electrode of the present invention has conductivity and can be wrapped on the surface of the barrier medium.

The material forming the central high-voltage electrode is a conductive material. Preferably, the material forming the central high-voltage electrode is selected from at least one of graphite tubes, metal rods, metal tubes and graphite rods. The metal rods and metal tubes may include simple metal rods, alloy metal rods, simple metal tubes, and alloy metal tubes. The material forming the central high-voltage electrode of the present invention may be other rod-shaped and tubular materials with conductive properties.

The present invention can maintain the temperature of the reactor with a jacket structure at, for example, 119-444.6°C by introducing a heat-conducting medium into the area between the outer wall of the inner cylinder and the inner wall of the outer cylinder to ensure the hydrogen sulfide The sulfur produced by the decomposition flows out of the discharge area in liquid form.

The high-throughput low-temperature plasma reactor of the present invention can also be loaded with a catalyst capable of catalyzing the decomposition of hydrogen sulfide into elemental sulfur and hydrogen, and the catalyst is preferably loaded in the inner cylinder of the reactor. The present invention has no special requirements on the loading volume and loading type of the catalyst, and the type of the catalyst may be any one or more of the catalysts disclosed in CN102408095A, CN101590410A and CN103495427A, for example.

The high-throughput low-temperature plasma reactor provided by the present invention has no special restrictions on the conditions of the decomposition reaction involved in the decomposition of hydrogen sulfide, and can be various methods involved in the plasma decomposition hydrogen sulfide method conventionally used in the art. Conditions to decompose, the embodiment part of the present invention exemplarily enumerates the conditions for decomposing hydrogen sulfide, those skilled in the art should not be understood as the limitation of the present invention.

As mentioned above, the second aspect of the present invention provides a method for decomposing hydrogen sulfide, the method is implemented in the high-flux low-temperature plasma reactor described in the first aspect, the method includes: Next, the raw material gas containing hydrogen sulfide is introduced from the reactor inlet into each reaction tube of the high-throughput low-temperature plasma reactor inner barrel to carry out the decomposition reaction of hydrogen sulfide, and the stream obtained after the decomposition is drawn out from the product outlet , and, by continuously introducing the heat-conducting medium into the outer cylinder of the high-flux low-temperature plasma reactor from the heat-conducting medium inlet and drawing out the heat-conducting medium from the heat-conducting medium outlet to maintain the high-flux low-temperature plasma reactor The dielectric barrier discharge is formed by the ground electrode, the barrier medium and the central high voltage electrode.

The high-throughput low-temperature plasma reactor provided by the present invention has no special restrictions on the conditions of the decomposition reaction involved in the decomposition of hydrogen sulfide, and can be various methods involved in the plasma decomposition hydrogen sulfide method conventionally used in the art. Conditions to decompose, the embodiment part of the present invention exemplarily enumerates the conditions for decomposing hydrogen sulfide, those skilled in the art should not be understood as the limitation of the present invention.

In the present invention, there is no particular limitation on the material forming the outer cylinder, as long as the material forming the outer cylinder can withstand the set temperature of the heat transfer medium.

The high-throughput low-temperature plasma reactor provided by the present invention has no special limitation on the concentration of hydrogen sulfide in the gas at the reactor inlet, for example, the concentration of hydrogen sulfide in the gas may be 0.01-100% by volume.

The structure of a preferred embodiment of the high-throughput low-temperature plasma reactor of the present invention is provided below in conjunction with Fig. 1, specifically:

The reactor has a jacketed sleeve structure, and the reactor includes:

The inner cylinder 1 is provided with a reactor inlet 11 and a product outlet respectively, and the inner cylinder 1 contains at least two reaction tubes 14 arranged side by side, and the top and bottom of each of the reaction tubes 14 are Respectively correspond to each other, so that the raw materials entering by the reactor inlet 11 can enter each of the reaction tubes 14 respectively, and the products produced in each of the reaction tubes 14 can be drawn out from the product outlet;

The outer cylinder 2, the outer cylinder 2 is nested outside the inner cylinder 1, and the outer cylinder 2 is respectively provided with a heat transfer medium inlet 21 and a heat transfer medium outlet 22, and the heat conduction medium introduced by the heat transfer medium inlet 21 The medium can be distributed between each of the reaction tubes 14 of the inner cylinder 1, and the heat-conducting medium is drawn out from the heat-conducting medium outlet 22;

a central high voltage electrode 3, the central high voltage electrode 3 is respectively arranged in each of the reaction tubes 14 of the inner cylinder 1;

Ground electrode 4, the material forming the ground electrode 4 is a solid conductive material, and the ground electrode 4 forms at least part of the side wall of each of the reaction tubes 14 or the ground electrode 4 is respectively arranged around each of the reaction tubes 14 on the outer wall;

A barrier medium, the barrier medium forms at least part of the side wall of each of the reaction tubes 14 so that at least part of the barrier medium surrounds the central high-voltage electrode 3, or the barrier medium is arranged around the inner side of each of the reaction tubes 14 on the wall;

In each of the reaction tubes 14, the barrier medium is positioned such that the discharge area between the central high voltage electrode and the ground electrode is separated by the barrier medium,

In each of the reaction tubes 14, the proportional relationship between the distance L1 between the outer sidewall of the central high-voltage electrode ₃ and the inner sidewall of the barrier medium and the thickness D1 _of the barrier medium is: L1 _: D ₁ = (0.05-100): 1.

Preferably, the barrier medium forms at least part of the side wall of each of the reaction tubes 14 so that at least part of the barrier medium surrounds the central high-voltage electrode 3, and the ground electrodes 4 are respectively arranged around each of the reaction tubes. 14 on the outer wall.

More preferably, all the side walls of each reaction tube 14 are formed by the barrier medium.

Preferably, in each of the reaction tubes 14, the proportional relationship between the distance L1 between the outer sidewall of the central high-voltage electrode ₃ and the inner sidewall of the barrier medium and the thickness D1 _of the barrier medium is: L ₁ :D ₁ =(0.1-30):1.

Preferably, the central high-voltage electrodes 3 in each of the reaction tubes 14 are connected in parallel with each other.

Preferably, the reactor further includes a grounding wire 5 , the grounding wire is arranged on the outer wall of the outer cylinder 2 , and one end thereof is connected to the grounding electrodes 4 in each of the reaction tubes 14 .

Preferably, the reactor inlet 11 is arranged at the upper part of the inner cylinder 1 , and the product outlet is arranged at the lower part and/or bottom of the inner cylinder 1 .

According to a preferred embodiment, the product outlet includes a gas product outlet 12 and a liquid product outlet 13, and the gas product outlet 12 is arranged at the lower part of the inner cylinder 1, and the liquid product outlet 13 is arranged at The bottom of the inner cylinder 1.

Preferably, the size of each of the reaction tubes 14 is the same.

Preferably, the gas product outlet 12 is arranged below the entire discharge area, and the gas product outlet ₁₂ is located at a height H1 relative to the bottom of the inner cylinder ₁ and a length L2 of the discharge area The proportional relationship between them is: H ₁ : L ₂ =1: (0.05-25000); preferably H ₁ : L ₂ =1: (0.1-10000); more preferably H ₁ : L ₂ =1: (0.5 ~1000).

Preferably, the heat-conducting medium inlet 21 and the heat-conducting medium outlet 22 are respectively arranged at the lower part and the upper part of the outer cylinder 2 .

Another preferred embodiment of applying the aforementioned high-throughput low-temperature plasma reactor of the present invention to decompose hydrogen sulfide is provided below:

Nitrogen gas is introduced into the inner barrel of the high-flux low-temperature plasma reactor from the reactor inlet to remove the air in the discharge area, and the gas is drawn out from the product outlet. At the same time, the heat transfer medium is introduced into the outer cylinder from the heat transfer medium inlet, and the introduced heat transfer medium is led out from the heat transfer medium outlet. The temperature of the heat transfer medium is maintained at the temperature required by the system reaction. Then feed raw material gas containing hydrogen sulfide from the reactor inlet to the inner cylinder of the high-throughput low-temperature plasma reactor, and the raw material gas fills each reaction tube. A plasma discharge field is formed between the central high voltage electrode and the ground electrode. The hydrogen sulfide gas is ionized in the discharge area and decomposed into hydrogen and elemental sulfur. The elemental sulfur produced by the discharge slowly flows down the inner cylinder wall and flows out from the product outlet.

The high-throughput low-temperature plasma reactor provided by the present invention also has the following specific advantages:

(1) The reactor uses a conductive solid material as the grounding electrode. Compared with the liquid grounding electrode, the micro-discharge current generated by the discharge when this grounding electrode cooperates with the structure of the present invention is larger, which is more conducive to the discharge decomposition reaction of hydrogen sulfide molecules .

(2) A jacket structure is set outside the ground electrode of the reactor, and the temperature of the reactor can be controlled by controlling the temperature of the heat-conducting medium in the jacket, so that the sulfur generated by the hydrogen sulfide discharge decomposition can flow out of the discharge area smoothly, and the sulfur solidification can be avoided to block the reaction device, so that the discharge continues and stably proceeds.

(3) The reactor controls the distance L ₁ between the outer wall of the central high-voltage electrode and the inner wall of the barrier medium and the proportional relationship between the thickness D ₁ of the barrier medium is: L ₁ : D ₁ = (0.05-100): 1; more preferably L ₁ : D ₁ = (0.1-30): 1, combined with the structure of the reactor of the present invention, can significantly increase the conversion rate of hydrogen sulfide and reduce energy consumption for decomposition.

The present invention will be described in detail below by way of examples. In the following examples, unless otherwise specified, all raw materials used are commercially available.

The conversion ratio of hydrogen sulfide in the following examples is calculated according to the following formula:

The thickness of the barrier medium in the following examples and comparative examples is the same.

The conversion rate of hydrogen sulfide% = the number of moles of converted hydrogen sulfide / the number of moles of initial hydrogen sulfide × 100%

In the following example, the energy consumption for decomposing hydrogen sulfide is obtained through oscilloscope detection and Lissajous graph calculation.

Example 1

The high-flux low-temperature plasma reactor shown in Figure 1 is used for hydrogen sulfide decomposition reaction. The specific structure and structural parameters of the high-flux low-temperature plasma reactor are as follows:

The reactor includes:

An inner cylinder, the inner cylinder is respectively provided with a reactor inlet, a gas product outlet and a liquid product outlet, and the inner cylinder contains 4 reaction tubes arranged side by side, and the top and bottom of each of the reaction tubes communicate with each other respectively , so that the raw materials entering by the reactor inlet can enter into each of the reaction tubes respectively, and the gaseous products produced in each of the reaction tubes can be drawn out from the gas product outlet, and each of the reaction tubes The liquid product produced in the reaction tube can be drawn out from the liquid product outlet, the size of the four reaction tubes is exactly the same, all the side walls of the reaction tube are formed by a barrier medium, and the material forming the barrier medium is hard glass;

An outer cylinder, the outer cylinder is nested outside the inner cylinder, and the outer cylinder is respectively provided with a heat transfer medium inlet and a heat transfer medium outlet, and the heat transfer medium introduced by the heat transfer medium inlet can be distributed in the inner cylinder Between each of the reaction tubes of the barrel, and the heat transfer medium is drawn out from the heat transfer medium outlet;

A central high-voltage electrode, the central high-voltage electrode is arranged at the central axis position of each of the reaction tubes, the material forming the central high-voltage electrode is a stainless steel metal rod, and the central high-voltage electrodes in each reaction tube are connected in parallel;

Grounding electrodes, the grounding electrodes are respectively arranged around the outer walls of each of the reaction tubes, the material forming the grounding electrodes is stainless steel metal foil, and the lower edge of the central high-voltage electrode in this embodiment is connected to the grounding electrode The lower edge is flush.

In each reaction tube, the ratio of the distance L1 between the outer wall of the central high _- voltage electrode and the inner wall of the barrier medium to the thickness D1 of the barrier medium is 8: ₁ ;

The ratio between the height H ₁ of the position of the gas product outlet relative to the bottom of the inner cylinder and the length L ₂ of the discharge area in each reaction tube is: H ₁ : L ₂ =1:32;

The volume of the entire reactor inner cylinder in this embodiment is 1L.

In this embodiment, the mixed gas enters the reactor inner cylinder from the upper part of the reactor inner cylinder, and the gas product is drawn out from the gas product outlet located at the lower part of the reactor inner cylinder, and the elemental sulfur is drawn out from the liquid product outlet located at the bottom of the reactor; and this The heat transfer medium of the embodiment is introduced from the lower part of the outer cylinder of the reactor, and drawn out from the upper part of the outer cylinder of the reactor.

Operation steps of high flux low temperature plasma reactor:

Nitrogen gas is introduced into the inner barrel of the high-flux low-temperature plasma reactor from the reactor inlet to remove the air in the discharge area, and the gas is drawn out from the gas product outlet and the liquid product outlet. At the same time, a heat transfer medium (specifically simethicone oil) is introduced into the outer cylinder from the heat transfer medium inlet, and the introduced heat transfer medium is led out from the heat transfer medium outlet, and the temperature of the heat transfer medium is kept at 145°C.

Then pass H2S/Ar mixed gas from the reactor inlet to the inner barrel of the high _- flux low _- temperature plasma reactor, wherein the H2S volume fraction is 65%, and the mixed gas flow rate is controlled so that the average residence time of the gas in the discharge area It is 9.7s. After the H ₂ S/Ar mixture gas was passed into the reactor for 30 minutes, the AC high-voltage power supply was switched on, and the plasma discharge field was formed between the central high-voltage electrode and the ground electrode by adjusting the voltage and frequency. The discharge conditions are as follows: the voltage is 13.8kV, the frequency is 0.8kHz, and the current is 2.2A. The hydrogen sulfide gas is ionized in the discharge area and decomposed into hydrogen and elemental sulfur. The elemental sulfur produced by the discharge slowly flows down the inner cylinder wall and flows out from the liquid product outlet. After the reaction, the gas flows out from the gas product outlet.

Results: After the hydrogen sulfide decomposition reaction in this example continued for 20 minutes, the conversion rate of H ₂ S was measured to be 73.6%; and no abnormality was found after continuous discharge for 100 hours, and the discharge state and conversion rate of H ₂ S remained stable. In addition, the decomposition energy consumption in this embodiment is 14.2eV/H ₂ S molecule (the energy required to decompose 1 molecule of H ₂ S is 14.2eV).

Comparative example 1

This comparative example adopts the high flux low temperature plasma reactor similar to embodiment 1 to carry out the hydrogen sulfide decomposition reaction, the difference is:

The grounding electrode in this comparative example is a liquid grounding electrode, and it is LiCl and AlCl ₃ in a molten state with a molar ratio of 1:1. The liquid grounding electrode is also a heat-conducting medium, and the temperature is kept at 145°C, and it is placed in the outer cylinder of the reactor. .

The flow rate of the mixed gas is controlled so that the average residence time of the gas in the discharge area is 20.5s.

The volume of the entire reactor inner cylinder of this comparative example is 0.05L.

All the other are the same as in Example 1.

And this comparative example adopts the same operation method as Example 1 to carry out the hydrogen sulfide decomposition reaction.

Results: The hydrogen sulfide decomposition reaction in this comparative example was continuously carried out for 20 minutes, and the conversion rate of H ₂ S was measured to be 14.9%, and the conversion rate of H ₂ S decreased to 6.9% after continuous discharge for 1.5 hours.

The decomposition energy consumption of this comparative example is 111eV/H ₂ S molecule.

Comparative example 2

This comparative example adopts the low-temperature plasma reactor similar to Comparative Example 1 to carry out, the difference is:

In each reaction tube, the ratio of the distance L ₁ between the outer wall of the central high-voltage electrode and the inner wall of the barrier medium to the thickness D ₁ of the barrier medium in this comparative example is 0.01:1.

The flow rate of the mixed gas is controlled so that the average residence time of the gas in the discharge area is 20.5s.

The volume of the inner cylinder of this comparative example is 0.02L.

The rest are the same as in Comparative Example 1.

Results: The hydrogen sulfide decomposition reaction in this comparative example was continuously carried out for 20 minutes, and the conversion rate of H ₂ S was measured to be 22.5%, and the conversion rate of H ₂ S decreased to 9.2% after continuous discharge for 1.5 hours.

The decomposition energy consumption of this comparative example is 143eV/H ₂ S molecule.

Example 2

In this embodiment, a high-throughput low-temperature plasma reactor similar to that of Embodiment 1 is used to carry out the decomposition reaction of hydrogen sulfide. The difference is that in this embodiment:

All side walls of the inner cylinder are formed by grounding electrodes, and the material for forming the grounding electrodes is stainless steel metal foil;

The blocking medium is arranged around the inner wall of the inner cylinder;

The ratio of the distance L1 between the outer sidewall of the central high-voltage electrode and the inner sidewall _of the barrier medium to the thickness D1 of the barrier medium is 18: ₁ ;

The proportional relationship between H ₁ and the length L ₂ of the discharge region containing the blocking medium is: H ₁ : L ₂ =1:95.

In this embodiment, H ₂ S/Ar mixed gas is introduced from the reactor inlet to the inner cylinder of the high-flux low-temperature plasma reactor, wherein the volume fraction of H ₂ S is 65%. The average residence time is 10.8s. After the H ₂ S/Ar mixture gas was passed into the reactor for 30 minutes, the AC high-voltage power supply was switched on, and the plasma discharge field was formed between the central high-voltage electrode and the ground electrode by adjusting the voltage and frequency. The discharge conditions are as follows: the voltage is 14.9kV, the frequency is 1.6kHz, and the current is 1.95A.

All the other are the same as in Example 1.

Results: After the hydrogen sulfide decomposition reaction in this example continued for 20 minutes, the conversion rate of H ₂ S was measured to be 74.2%; and no abnormality was found after continuous discharge for 100 hours, and the discharge state and conversion rate of H ₂ S remained stable. And the decomposition energy consumption in this embodiment is 14.8eV/H ₂ S molecule.

Example 3

In this embodiment, a high-throughput low-temperature plasma reactor similar to that of Embodiment 1 is used to carry out the decomposition reaction of hydrogen sulfide. The difference is that in this embodiment:

All side walls of the inner cylinder are formed by ground electrodes, and the material for forming the ground electrodes is copper foil;

The blocking medium is arranged around the inner wall of the inner cylinder;

The ratio of the distance L1 between the outer sidewall of the central high-voltage electrode and the inner sidewall _of the barrier medium to the thickness D1 of the barrier medium is 0.5: ₁ ;

The proportional relationship between H ₁ and the length L ₂ of the discharge region containing the blocking medium is: H ₁ : L ₂ =1:220.

In this embodiment, H ₂ S/Ar mixed gas is introduced from the reactor inlet to the inner cylinder of the high-flux low-temperature plasma reactor, wherein the volume fraction of H ₂ S is 65%. The average residence time is 8.2s. After the H ₂ S/Ar mixture gas was passed into the reactor for 30 minutes, the AC high-voltage power supply was switched on, and the plasma discharge field was formed between the central high-voltage electrode and the ground electrode by adjusting the voltage and frequency. The discharge conditions are as follows: the voltage is 8.0kV, the frequency is 2.3kHz, and the current is 1.5A.

All the other are the same as in Example 1.

Results: After the hydrogen sulfide decomposition reaction in this example continued for 20 minutes, the conversion rate of H ₂ S was measured to be 74.0%; and no abnormality was found after continuous discharge for 100 hours, and the discharge state and conversion rate of H ₂ S remained stable. And the decomposition energy consumption in this embodiment is 15.6eV/H ₂ S molecule.

Example 4

The present embodiment adopts the plasma reactor similar to embodiment 1 to carry out the decomposition reaction of hydrogen sulfide, the difference is, in the present embodiment:

The ratio of the distance L ₁ between the outer sidewall of the central high voltage electrode and the inner sidewall of the barrier medium to the thickness D ₁ of the barrier medium is 35:1.

All the other are the same as in Example 1.

Results: After the hydrogen sulfide decomposition reaction in this example continued for 20 minutes, the conversion rate of H ₂ S was measured to be 67.2%; and no abnormality was found after continuous discharge for 100 hours, and the discharge state and conversion rate of H ₂ S remained stable. And the decomposition energy consumption in this embodiment is 23.6eV/H ₂ S molecule.

As can be seen from the above results, when the high-throughput low-temperature plasma reactor provided by the present invention is used to decompose hydrogen sulfide, the conversion rate of hydrogen sulfide can be significantly improved relative to the prior art, and the reactor provided by the present invention can be used in Maintain a high conversion rate of hydrogen sulfide for a long period of time with low decomposition energy consumption.

The preferred embodiments of the present invention have been described in detail above, however, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the disclosed content of the present invention. All belong to the protection scope of the present invention.

Claims (13)

1. a kind of high throughput reaction of low temperature plasma device, which has collet core structure, and the reactor includes:

Inner cylinder (1) is respectively arranged with reactor inlet (11) and product exit, also, the inner cylinder (1) on the inner cylinder (1) In the reaction tube (14) that is set side by side containing at least two, respectively correspond phase at the top and bottom of each reaction tube (14) It is logical, the raw material entered by the reactor inlet (11) is had respectively entered in each reaction tube (14), and The middle product generated of each reaction tube (14) is drawn by the product exit；

Outer cylinder (2), the outer cylinder (2) are nested in the outside of the inner cylinder (1), and are respectively arranged on the outer cylinder (2) thermally conductive Medium inlet (21) and heat-conducting medium outlet (22), can be distributed in by the heat-conducting medium that the heat-conducting medium entrance (21) introduces Between each reaction tube (14) of the inner cylinder (1), and the heat-conducting medium exports (22) by the heat-conducting medium and draws Out；

Central high pressure electrode (3), the central high pressure electrode (3) are separately positioned on each reaction tube of the inner cylinder (1) (14) in；

Grounding electrode (4), the material for forming the grounding electrode (4) is solid conductive material, and the grounding electrode (4) is formed At least partly side wall or the grounding electrode (4) of each reaction tube (14) are circumferentially positioned at each reaction respectively On the lateral wall for managing (14)；

Block media, at least partly side wall that the block media forms each reaction tube (14) make at least partly described Block media is circumferentially positioned at each reaction tube (14) around the central high pressure electrode (3) or the block media Inner sidewall on；

In each reaction tube (14), the setting position of the block media makes the central high pressure electrode and described connects Region of discharge between ground electrode by the block media interval,

In each reaction tube (14), the lateral wall of the central high pressure electrode (3) and the inner sidewall of the block media The distance between L₁With the thickness D of the block media₁Proportionate relationship are as follows: L₁: D₁=(0.05~100): 1.

2. high throughput reaction of low temperature plasma device according to claim 1, wherein the block media forms each institute At least partly side wall for stating reaction tube (14) makes at least partly described block media around the central high pressure electrode (3), and The grounding electrode (4) is circumferentially positioned at respectively on the lateral wall of each reaction tube (14)；Preferably,

The side wall of each reaction tube (14) is all formed by the block media.

3. high throughput reaction of low temperature plasma device according to claim 1 or 2, wherein L₁: D₁=(0.1~30): 1.

4. high-throughput reaction of low temperature plasma device described in any one of -3 according to claim 1, wherein each described anti- The central high pressure electrode (3) that should be managed in (14) is connected in parallel with each other.

5. high-throughput reaction of low temperature plasma device described in any one of -3 according to claim 1, wherein form the resistance The material for keeping off medium is electrically insulating material；Preferably,

Form at least one of the material of the block media in glass, quartz, ceramics, enamel, polytetrafluoroethylene (PTFE) and mica Kind.

6. high-throughput reaction of low temperature plasma device described in any one of -3 according to claim 1, wherein the reactor is also Including ground line (5), the ground line is arranged on the lateral wall of the outer cylinder (2), and one end and each reaction tube (14) grounding electrode (4) connection in.

7. high-throughput reaction of low temperature plasma device described in any one of -3 according to claim 1, wherein the reactor Entrance (11) setting is arranged in the top of the inner cylinder (1), the product exit in the lower part and/or bottom of the inner cylinder (1)； Preferably,

The product exit includes product gas outlet (12) and liquid product outlet (13), and the product gas outlet (12) It is arranged and is arranged in the lower part of the inner cylinder (1) and the liquid product outlet (13) in the bottom of the inner cylinder (1).

8. high-throughput reaction of low temperature plasma device described in any one of -3 according to claim 1, wherein each described anti- The size that (14) should be managed is identical.

9. high throughput reaction of low temperature plasma device according to claim 7, wherein the product gas outlet (12) sets It sets in the lower section of the region of discharge, and the setting position of the product gas outlet (12) is relative to the inner cylinder (1) bottom Height H₁With the length L of the region of discharge₂Between proportionate relationship are as follows: H₁: L₂=1:(0.05~25000)；Preferably H₁: L₂=1:(0.1~10000)；More preferably H₁: L₂=1:(0.5~1000).

10. high-throughput reaction of low temperature plasma device described in any one of -3 according to claim 1, wherein described thermally conductive Medium inlet (21) and heat-conducting medium outlet (22) are separately positioned on the lower part and top of the outer cylinder (2).

11. high throughput reaction of low temperature plasma device according to claim 1, wherein form the grounding electrode (4) Material is selected from graphite-pipe, metal tube, metal foil or metal mesh.

12. high throughput reaction of low temperature plasma device according to claim 1, wherein form the central high pressure electrode (3) material is selected from least one of graphite-pipe, metal bar, metal tube and graphite rod.

13. a kind of method of decomposing hydrogen sulfide, high-throughput low temperature etc. of this method described in any one of claim 1-12 Implement in plasma reactor, this method comprises: under the conditions of dielectric barrier discharge, by the unstripped gas containing hydrogen sulfide from reaction The decomposition that device entrance is introduced to progress hydrogen sulfide in each reaction tube of the high-throughput reaction of low temperature plasma device inner cylinder is anti- It answers, the logistics obtained after decomposition is drawn by the product exit, also, by continuing from heat-conducting medium entrance to the high throughput Heat-conducting medium is introduced in the outer cylinder of reaction of low temperature plasma device and is drawn the heat-conducting medium by heat-conducting medium outlet and is tieed up Temperature needed for holding the high-throughput reaction of low temperature plasma device, the dielectric barrier discharge is by grounding electrode, block media It is formed with central high pressure electrode.