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CN-110124469-B - High flux plasma reaction apparatus and method for decomposing hydrogen sulfide

CN110124469BCN 110124469 BCN110124469 BCN 110124469BCN-110124469-B

Abstract

The invention relates to the field of plasma chemistry, and discloses a high-flux plasma reaction device and a method for decomposing hydrogen sulfide, wherein the high-flux plasma reaction device comprises an inner cylinder (1) containing reaction tubes (14), an outer cylinder (2) nested outside the inner cylinder (1), a central high-voltage electrode (3), grounding electrodes (4) respectively arranged on the outer side walls of the reaction tubes (14) in a surrounding mode or forming side walls, a blocking medium (6) arranged on at least part of the outer surfaces of the central high-voltage electrode (3), and a proportional relation between a distance L 1 between the outer side walls of the blocking medium and the inner side walls of the grounding electrodes and a length L 2 of a discharge area is L 1 ：L 2 =1 (0.5-6000). The high-flux plasma reaction device provided by the invention can realize continuous and stable hydrogen sulfide decomposition process under obviously higher hydrogen sulfide conversion rate, and the device can realize long-period operation.

Inventors

  • ZHANG JING
  • JIANG CHUNMING
  • ZHANG TIE
  • REN JUNPENG
  • SUN FENG
  • JIN MANPING
  • XU WEI
  • SHI NING

Assignees

  • 中国石油化工股份有限公司
  • 中国石油化工股份有限公司青岛安全工程研究院

Dates

Publication Date
20260505
Application Date
20180209

Claims (10)

  1. 1. A high throughput plasma reaction apparatus having a jacketed cartridge type structure, the reaction apparatus comprising: The reactor comprises an inner cylinder (1), wherein a reactor inlet (11) and a product outlet (13) are respectively arranged on the inner cylinder (1), the inner cylinder (1) comprises at least two reaction tubes (14) which are arranged in parallel, and the top and the bottom of each reaction tube (14) are respectively communicated correspondingly, so that raw materials entering from the reactor inlet (11) can respectively enter each reaction tube (14), and products generated in each reaction tube (14) can be led out from the product outlet; An outer cylinder (2), wherein the outer cylinder (2) is nested outside the inner cylinder (1), a heat conducting medium inlet (21) and a heat conducting medium outlet (22) are respectively arranged on the outer cylinder (2), the heat conducting medium introduced by the heat conducting medium inlet (21) can be distributed among the reaction tubes (14) of the inner cylinder (1), and the heat conducting medium is led out from the heat conducting medium outlet (22); a central high-voltage electrode (3), wherein the central high-voltage electrode (3) is respectively arranged in each reaction tube (14) of the inner cylinder (1); The grounding electrode (4) is made of solid conductive materials, the grounding electrode (4) is respectively arranged on the inner side wall of each reaction tube (14) in a surrounding mode, or the grounding electrode (4) respectively forms at least part of the side wall of each reaction tube (14); a blocking medium (6), wherein the blocking medium (6) is arranged on at least part of the outer surface of the central high-voltage electrode (3) so that the blocking medium (6) is wrapped on the outer surface of the central high-voltage electrode (3) which at least partially stretches into the inner cylinder (1); Wherein, in each reaction tube (14), the arrangement position of the blocking medium (6) is that the discharge area between the center high-voltage electrode and the grounding electrode is separated by the blocking medium, and the proportional relation between the distance L 1 between the outer side wall of the blocking medium (6) and the inner side wall of the grounding electrode and the length L 2 of the discharge area is that L 1 ：L 2 =1 (300-3000); the proportional relation between the distance L 1 between the outer side wall of the blocking medium (6) and the inner side wall of the grounding electrode and the thickness D 1 of the blocking medium is L 1 ：D 1 = (0.5-15) 1; 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 the bottom of the inner cylinder (1); The product outlet comprises a gas product outlet (12) and a liquid product outlet (13), the gas product outlet (12) is arranged at the lower part of the inner cylinder (1), the liquid product outlet (13) is arranged at the bottom of the inner cylinder (1), the gas product outlet (12) is arranged below all the discharge areas, and the proportion relation between the arrangement position of the gas product outlet (12) relative to the height H 1 of the bottom of the inner cylinder (1) and the length L 2 of the discharge areas is that H 1 ：L 2 =1 (0.5-1000).
  2. 2. A high-flux plasma reaction device according to claim 1, wherein the central high-voltage electrodes (3) in each of the reaction tubes (14) are connected in parallel with each other.
  3. 3. A high flux plasma reaction apparatus according to claim 1 or claim 2 wherein the material forming the blocking medium is an electrically insulating material.
  4. 4. A high-throughput plasma reaction apparatus as claimed in claim 3 wherein the material forming the blocking medium is selected from at least one of glass, quartz, ceramic, enamel, polytetrafluoroethylene and mica.
  5. 5. A high flux plasma reaction apparatus according to claim 1 or 2, wherein the reaction apparatus further comprises a ground wire (5) provided on the outer side wall of the outer cylinder (2) and electrically connected at one end to the ground electrode (4) in each of the reaction tubes (14).
  6. 6. A high-throughput plasma reaction apparatus as claimed in claim 1 or claim 2, wherein the dimensions of each of the reaction tubes (14) are the same.
  7. 7. The high-flux plasma reaction device of claim 1 or 2, wherein the heat transfer medium inlet (21) and the heat transfer medium outlet (22) are provided at a lower portion and an upper portion of the outer tub (2), respectively.
  8. 8. A high-flux plasma reaction apparatus according to claim 1, wherein the material forming the ground electrode (4) is selected from a graphite tube, a metal foil or a metal mesh.
  9. 9. The high-flux plasma reaction apparatus of claim 1, wherein the material forming the central high-voltage electrode (3) is selected from at least one of graphite tube, metal rod, metal tube, graphite powder, metal powder and graphite rod.
  10. 10. A method of decomposing hydrogen sulfide, which is carried out in the high-flux plasma reaction apparatus as claimed in any one of claims 1 to 9, comprising introducing a raw material gas containing hydrogen sulfide into a reaction tube of an inner tube of the high-flux plasma reaction apparatus from a reactor inlet under a dielectric barrier discharge condition, performing a decomposition reaction of hydrogen sulfide, and withdrawing a stream obtained after the decomposition from the product outlet, and maintaining a temperature required for the high-flux plasma reaction apparatus by continuously introducing a heat-conducting medium into an outer tube of the high-flux plasma reaction apparatus from a heat-conducting medium inlet and withdrawing the heat-conducting medium from a heat-conducting medium outlet, the dielectric barrier discharge being formed by a ground electrode, a barrier medium, and a central high-voltage electrode in each of the reaction tubes.

Description

High flux plasma reaction apparatus and method for decomposing hydrogen sulfide Technical Field The invention relates to the field of plasma chemistry, in particular to a high-flux plasma reaction device and a method for decomposing hydrogen sulfide. Background Hydrogen sulfide (H 2 S) is a highly toxic and malodorous acid gas, which not only causes corrosion of materials such as metal, but also causes harm to human health and environmental pollution. At present, large and medium-sized refineries in China all adopt the traditional Claus method (Claus) to treat tail gas containing H 2 S and recover sulfur. This process recovers only the sulfur from the hydrogen sulfide, but converts the valuable hydrogen to water. From the standpoint of comprehensive utilization of resources, hydrogen resources are not utilized effectively in the conventional hydrogen sulfide recovery process. Therefore, the decomposition of hydrogen sulfide into sulfur and hydrogen gradually becomes a technical field of great attention of scientific researchers at home and abroad. At present, the hydrogen sulfide decomposition method mainly comprises a high-temperature decomposition method, an electrochemical method, a photocatalysis method, a low-temperature plasma method and the like. Among the aforementioned various methods, the high-temperature pyrolysis method is relatively mature in industrial technology, but the thermal decomposition of hydrogen sulfide is strongly dependent on the reaction temperature and limited by the thermodynamic equilibrium, and the conversion rate of hydrogen sulfide is only 20% even if the reaction temperature is above 1000 ℃. In addition, high temperature conditions place high demands on the reactor materials, which also increases operating costs. In addition, since the conversion rate of the thermal decomposition of hydrogen sulfide is low, a large amount of hydrogen sulfide gas needs to be separated from the tail gas and circulated in the system, so that the efficiency of the device is also reduced and the energy consumption is increased, which all have difficulty in large-scale industrial application thereof. Although the membrane technology can effectively separate the product, thereby breaking the balance limit and improving the conversion rate of hydrogen sulfide, the thermal decomposition temperature often exceeds the limit heat-resistant temperature of the membrane, so that the structure of the membrane material is damaged. The electrochemical method has the defects of more operation steps, serious equipment corrosion, poor reaction stability, low efficiency and the like. The photocatalytic method for decomposing hydrogen sulfide is mainly used for researching photocatalytic water decomposition, and research focuses on the aspects of developing efficient semiconductor photocatalysts and the like. The method for decomposing the hydrogen sulfide by utilizing the solar energy has the advantages of low energy consumption, mild reaction conditions, simple operation and the like, and is a relatively economical method. However, this method has problems such as small throughput, low catalytic efficiency, and easy catalyst deactivation. Compared with other decomposition methods, the low-temperature plasma method has the advantages of simple operation, small device volume, high energy efficiency and the like, and the reaction involved in the method has high controllability and can be flexibly applied under the conditions of small treatment capacity and difficult centralized treatment. In addition, due to the characteristics of high energy density and shortened reaction time, the method can effectively decompose the hydrogen sulfide at a lower temperature, and is suitable for occasions with different scales, distributed layout and changeable production conditions. In addition, the low-temperature plasma method recovers hydrogen resources while recovering sulfur, and can realize the utilization of hydrogen sulfide resources. At present, researchers at home and abroad widely study the low-temperature plasma hydrogen sulfide decomposition technology, and the discharge modes mainly comprise glow discharge, corona discharge, sliding arc discharge, microwave plasma, radio-frequency plasma, dielectric barrier discharge and the like. And (3) decomposing hydrogen sulfide by adopting a shrinkage normal glow discharge method in a literature International journal of hydrogen energy, 2012,37:1335-1347, and obtaining the minimum decomposition energy consumption of the hydrogen sulfide of 2.35eV/H 2 S under the conditions of the pressure of 0.02Mpa and the temperature of 2000-4000K. However, the reaction temperature is high, the pressure is low, and the conditions are harsh and are not easy to realize. The document International journal of hydrogen energy, 2012,37:10010-10019 adopts microwave plasma to decompose hydrogen sulfide, and the hydrogen sulfide can be completely decomposed under the conditions of atmospheric pressur