Apparatus and method for removing elemental mercury by electrically exploding a metal wire

Abstract

The application discloses a device and a method for removing elemental mercury by electric explosion of metal wires, which is composed of a wire supply mechanism, a wire clamping cylinder, a wire pulling cylinder, a positive high-voltage electrode, a negative high-voltage electrode, a reaction cavity, a high-voltage power supply, a high-voltage capacitor and a controller. The high-voltage power supply charges the high-voltage capacitor, the wire pulling cylinder pulls the metal wire from the wire supply mechanism into the reaction cavity, the wire clamping cylinder fixes the metal wire, the positive high-voltage electrode and the negative high-voltage electrode contact the metal wire, the high-voltage capacitor discharges the metal wire through the positive high-voltage electrode and the negative high-voltage electrode, high voltage and large current make the metal wire heat, melt, vaporize, explode and form iron vapor mist, the iron vapor mist condenses into nano-powder mist area of iron-based compounds such as nano-iron particles and nano-iron oxide particles in the waste gas, and the elemental mercury in the waste gas is removed after the iron-based compound nano-powder particles in the mist area fully contact with the elemental mercury.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of preparing nanometer active metal powder by electric explosion, in particular to a device and method for removing elemental mercury by electric explosion of metal wires. BACKGROUND

[0002] Nanometer active metal powder is prepared by directly electric explosion of metal wires with high-voltage discharge, overload fusing, explosion into molten metal, rapid cooling with the end of explosion, and condensation into nanometer particles. This technology has been studied, but is still in the primary stage. The device design, layout of components, and effect adjustability still need to be further optimized. The preparation of nanometer active metal powder by electric explosion of metal wires still needs to enhance the control of various indicators of the product. The existing technology still needs to enhance the adjustment of the composition, shape, and particle size distribution of nanometer metal powder, and the subsequent use path of the product still needs to be developed. Several documents have reported the chemical activity of nanometer active metal powder to oxidize elemental mercury and remove mercury from waste gas. However, this method is high in cost, complex in use, limited in mercury removal efficiency and scale, and generally exists in the laboratory stage. The above methods are difficult to achieve dynamic and effective removal of mercury in large amounts of waste gas under complex working conditions, and cannot achieve efficient removal of mercury under the premise of ensuring the economic efficiency of the overall process design.

[0003] To solve this problem, the present application uses an automatic electric explosion of metal wire device to prepare nanometer active metal powder in real time by electric explosion method, and reasonably designs the process and method for removing elemental mercury from waste gas, which can achieve efficient, stable, automatic, and economic removal of mercury. SUMMARY

[0004] The purpose of the present application is to provide a device and method for removing elemental mercury by electric explosion of metal wires to solve the problems existing in the prior art.

[0005] To achieve the above purpose, the present application provides the following solutions:

[0006] The utility model provides an apparatus for removing elemental mercury by electric explosion of metal wire, comprising a wire supply mechanism, a wire clamping cylinder, a wire pulling cylinder, a positive high voltage electrode, a negative high voltage electrode, a reaction shell, a high voltage power supply, a high voltage capacitor and a controller, wherein the reaction shell is a hollow structure, the inner cavity of the reaction shell is a reaction chamber, the wire supply mechanism is arranged on one side of the reaction shell and is used to output metal wire, one end of the metal wire penetrates through the reaction shell and is detachably connected with the wire clamping cylinder and the wire pulling cylinder respectively, the high voltage power supply is arranged on the other side of the reaction shell, the high voltage power supply is electrically connected with a high voltage capacitor, the high voltage capacitor is electrically connected with a negative high voltage electrode and a positive high voltage electrode respectively, the negative high voltage electrode and the positive high voltage electrode penetrate through the side wall of the reaction shell and intermittently contact the side surface of the metal wire respectively, and one end of the reaction shell is provided with an air inlet hole and the other end of the reaction shell is provided with an air outlet hole.

[0007] Preferably, the air inlet hole is arranged close to the wire pulling cylinder, and the air outlet hole is arranged close to the wire clamping cylinder.

[0008] Preferably, the metal wire is an iron wire with a diameter of 0.5 mm and an iron element content of more than 99.5%.

[0009] Preferably, the charging voltage of the high voltage power supply to the high voltage capacitor is 35 KV or more, the distance between the negative high voltage electrode and the positive high voltage electrode is 200 mm, the distance between the negative high voltage electrode and the wire clamping cylinder is 30 mm, and the distance between the positive high voltage electrode and the wire pulling cylinder is 30 mm.

[0010] A method for using an apparatus for removing elemental mercury by electric explosion of metal wire, comprising the following steps:

[0011] S1, a pretreatment process, wherein waste gas containing mercury is introduced into a reaction chamber from an air inlet hole;

[0012] S2, an electric explosion process for removing elemental mercury, wherein active metal wire is used, and by controlling the ordered contact between the negative high voltage electrode, the positive high voltage electrode and the metal wire, nanometer active metal powder with appropriate particle size, active properties and slow settling speed is obtained to remove elemental mercury from the waste gas introduced in S1;

[0013] S3, a gas-solid separation process, wherein wet method is used to separate the waste gas and waste solid particles generated in step S2;

[0014] S4, a gas purification process, wherein a gas deep purification process is used to purify residual other pollutants in the remaining gas after step S3.

[0015] The utility model has the following technical effects:

[0016] The present application utilizes high-voltage discharge on the metal wire to make the metal wire explode and form a large amount of fine powder, and the high-activity metal powder contacts with the elemental mercury in the waste gas to react with the elemental mercury vapor to form solid particles, thereby realizing the purification of the waste gas.

[0017] The waste gas mercury removal process of the present application can sufficiently purify the mercury-containing waste gas of a factory, separate the pollutants, and realize the environmental protection emission. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description only represent some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort based on these drawings.

[0019] Fig. 1 The present application is a structural schematic diagram.

[0020] Fig. 2 The present application is a process route diagram.

[0021] 1, reaction cavity; 2, exhaust hole; 3, negative high-voltage electrode; 4, high-voltage capacitor; 5, high-voltage power supply; 6, positive high-voltage electrode; 7, air inlet hole; 8, wire drawing cylinder; 9, metal wire; 10, wire clamping cylinder; 11, wire feeding mechanism. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments only represent some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without any creative effort fall within the scope of the present application.

[0023] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail in combination with the drawings and specific embodiments.

[0024] By Figs. 1-2The device for removing elemental mercury by electric explosion of metal wire shown in the application comprises a wire feeding mechanism 11, a wire clamping cylinder 10, a wire pulling cylinder 8, a positive high-voltage electrode 6, a negative high-voltage electrode 3, a reaction shell, a high-voltage power supply 5, a high-voltage capacitor 4 and a controller. The reaction shell is a hollow structure, and the inner cavity of the reaction shell is a reaction chamber 1. The wire feeding mechanism 11 is arranged on one side of the reaction shell and is used to output metal wire 9. One end of the metal wire 9 penetrates through the reaction shell and is detachably connected with the wire clamping cylinder 10 and the wire pulling cylinder 8. The high-voltage power supply 5 is arranged on the other side of the reaction shell. The high-voltage power supply 5 is electrically connected with the high-voltage capacitor 4. The high-voltage capacitor 4 is electrically connected with the negative high-voltage electrode 3 and the positive high-voltage electrode 6, respectively. The negative high-voltage electrode 3 and the positive high-voltage electrode 6 penetrate through the side wall of the reaction shell and intermittently contact the side surface of the metal wire 9. An air inlet hole 7 is arranged at one end of the reaction shell, and an air outlet hole 2 is arranged at the other end of the reaction shell. The air inlet hole 7 is arranged close to the wire pulling cylinder 8, and the air outlet hole 2 is arranged close to the wire clamping cylinder 10. The metal wire 9 is preferably an iron wire with a diameter of 0.5 mm and an iron element content of more than 99.5%. The charging voltage of the high-voltage capacitor 4 given by the high-voltage power supply 5 is 35 KV or more. The distance between the negative high-voltage electrode 3 and the positive high-voltage electrode 6 is 200 mm. The distance between the negative high-voltage electrode 3 and the wire clamping cylinder 10 is 30 mm. The distance between the positive high-voltage electrode 6 and the wire pulling cylinder 8 is 30 mm.

[0025] Further, the wire feeding mechanism 11 adopts an automatic control system, which can realize automatic operation of the working process of the device, adjust the explosion length, diameter and explosion space point of the metal wire, change the physicochemical properties of the metal powder obtained by electric explosion, and finally adapt to the on-site conditions of different mercury removal applications.

[0026] A use method of a device for removing elemental mercury by electric explosion of metal wire, comprising the following steps:

[0027] S1, a pretreatment process; waste gas containing mercury is introduced into the reaction chamber 1 from the air inlet hole 7;

[0028] S2, an electric explosion removal elemental mercury process; active metal wire 9 is adopted, and by controlling the orderly contact of the negative high-voltage electrode 3, the positive high-voltage electrode 6 and the metal wire 9, nanometer active metal powder with appropriate particle size, active properties and slow settling can be obtained to remove elemental mercury from the waste gas introduced in S1;

[0029] S3, a gas-solid separation process; a wet method is used to separate the waste gas and waste solid particles generated in step S2;

[0030] S4, a gas purification process; a gas deep purification process is used to purify residual other pollutants in the remaining gas after step S3.

[0031] The application needs to connect the air inlet hole 7 with the exhaust emission facility and communicate in the pretreatment process of step S1. Before the mercury-containing exhaust gas is introduced into the reaction cavity 1, the exhaust gas needs to be pretreated. The treatment process includes common gas pretreatment processes such as dust removal, acid removal, mist removal, and nitrogen removal. By strictly controlling the parameters such as water content, dust content, acidity, etc. (preferably, dust content ≤180 mg / m 3 , humidity ≤30-40%, temperature ≤50-90℃, gas volume ≤500 m 3 / h, hydrogen chloride ≤150 mg / m 3 ), the final purpose is to ensure the normal operation of the electric explosion mercury removal device. The mercury-containing exhaust gas is introduced into the reaction cavity 1 through the air inlet hole 7.

[0032] When the exhaust gas containing elemental mercury is introduced into the reaction cavity 1, the negative high-voltage electrode 3 and the positive high-voltage electrode 6 are driven by the telescopic mechanism to approach and contact the metal wire 9. At this time, the negative high-voltage electrode 3 and the positive high-voltage electrode 6 are electrically connected with the high-voltage capacitor 4, and the voltage between the negative high-voltage electrode 3 and the positive high-voltage electrode 6 is 35KV. At the moment when the negative high-voltage electrode 3 and the positive high-voltage electrode 6 respectively contact the metal wire 9, the part of the metal wire 9 that contacts the negative high-voltage electrode 3 and the positive high-voltage electrode 6 will explode, and the nanometer active metal powder with appropriate particle size, active properties, and slow settling will react with the elemental mercury in the exhaust gas to generate solid particle powder, achieving the removal of elemental mercury. The telescopic mechanism is preferably a high-precision electric cylinder that can realize fixed-distance telescoping. It is prior art and will not be described here.

[0033] After a section of the metal wire 9 explodes into powder, the wire feeding mechanism 11 will supply a section of the metal wire 9 at a fixed distance. At this time, the chuck of the wire clamping cylinder 10 will loosen, and the metal wire 9 will pass through the chuck of the wire clamping cylinder 10 to the wire drawing cylinder 8. The chuck of the wire drawing cylinder 8 clamps the end of the metal wire 9, and the chuck of the wire clamping cylinder 10 also clamps the metal wire 9 at the same time to avoid the movement of the metal wire 9 caused by the contact of the negative high-voltage electrode 3 and the positive high-voltage electrode 6, which leads to insufficient explosion.

[0034] During the electric explosion process, the higher voltage value charged into the high-voltage capacitor 4 by the high-voltage power supply 5 can promote the formation of smaller nanometer metal particles from the explosion of the metal wire 9. The diameter of the metal wire 9 can also be reduced to promote the formation of smaller nanometer metal particles from the explosion. The distance between the negative high-voltage electrode 3 and the positive high-voltage electrode 6 can also be reduced to promote the formation of smaller nanometer metal particles from the explosion. The smaller the metal particles, the more intense and sufficient the reaction with elemental mercury in the exhaust gas, and the higher the purification rate.

[0035] The waste gas after the process of electric explosion removal of elemental mercury contains part of nano metal powder (carried out by air flow), oxidized valence mercury components, residual other pollution components (and products after reaction with nano metal), etc. Therefore, gas purification needs to be carried out by gas-solid separation. The method used is wet gas-solid separation, and the gas is introduced into a grid tower (or spray tower) containing a reagent solution, and the metal powder is introduced into the liquid to realize separation. The reagent solution can realize efficient absorption of valence mercury, and other pollution components can also be partially absorbed by the reagent solution, so as to realize gas-solid separation. It is prior art, and will not be described here.

[0036] In the gas purification process, the gas in the S4 step has been basically purified. In order to remove residual other pollutants (POPs, dioxins, etc.) in the gas, a gas deep purification process is used. The process is preferably low-temperature plasma treatment or heat treatment or burning treatment or discharge treatment or chemical catalytic treatment or adsorbent treatment, etc., which can realize the bond breaking and decomposition of residual pollutants such as dioxins. The specific process is determined according to the overall device and the site working condition.

[0037] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0038] The above embodiments only describe the preferred modes of the present application, and do not limit the scope of the present application. Without departing from the design spirit of the present application, various modifications and improvements of the technical solutions of the present application made by those skilled in the art shall fall within the protection scope determined by the claims of the present application.

Claims

1. A device for removing elemental mercury by electro-explosive wire, characterized in that, The utility model relates to a kind of high-pressure electric field mercury removal device, including wire supply mechanism (11), wire clamping cylinder (10), wire drawing cylinder (8), positive high voltage electrode (6), negative high voltage electrode (3), reaction shell, high voltage power supply (5), high voltage capacitor (4), controller;The reaction shell is hollow structure, and the reaction shell inner chamber is reaction cavity (1), the wire supply mechanism (11) is arranged in one side of the reaction shell, and the wire supply mechanism (11) is used to output metal wire (9), one end of the metal wire (9) penetrates the reaction shell and is respectively detachably connected with the wire clamping cylinder (10), the wire drawing cylinder (8);The high voltage power supply (5) is arranged in the other side of the reaction shell, and the high voltage power supply (5) is electrically connected with high voltage capacitor (4), and the high voltage capacitor (4) is respectively electrically connected with negative high voltage electrode (3), positive high voltage electrode (6), and the negative high voltage electrode (3), the positive high voltage electrode (6) penetrates the side wall of the reaction shell respectively and intermittently contacts with the side surface of the metal wire (9);One end of the reaction shell is provided with air inlet hole (7), and the other end of the reaction shell is provided with air outlet hole (2); The air inlet hole (7) is close to the wire drawing cylinder (8) and is arranged, and the air outlet hole (2) is close to the wire clamping cylinder (10) and is arranged; The metal wire (9) is iron wire with diameter of 0.5mm and iron element content of 99.5% or more.

2. The apparatus for removing elemental mercury by electrically exploding metal wires according to claim 1, wherein: The charging voltage of the high voltage power supply (5) to the high voltage capacitor (4) is 35KV or more, the distance between the negative high voltage electrode (3) and the positive high voltage electrode (6) is 200mm, the distance between the negative high voltage electrode (3) and the wire clamping cylinder (10) is 30mm, and the distance between the positive high voltage electrode (6) and the wire drawing cylinder (8) is 30mm.

3. A method of using the apparatus for removing elemental mercury by electrically exploding metal wires according to any one of claims 1-2, characterized in that: It includes the following steps: S1, pretreatment process; the waste gas containing mercury is introduced into the reaction cavity (1) from the air inlet hole (7); S2, elemental mercury removal process by electric explosion; by controlling the ordered contact of the negative high voltage electrode (3), the positive high voltage electrode (6) and the metal wire (9), the nanometer active metal powder with suitable particle size, active property and slow settling can be obtained to remove the elemental mercury in the waste gas introduced in S1; S3, gas-solid separation process; the waste gas and waste solid particles generated in step S2 are separated by using wet method; S4, gas purification process; the residual other pollutants in the remaining gas after step S3 are purified by using gas deep purification process.

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