KR102598003B1 - Toxic gas obtained by metal acid treatment removal device and method of the toxic gas using the device - Google Patents

Abstract

The present invention solves the problems of existing technology and improves the removal device developed by the present inventor by installing an additional boiler to improve the efficiency of toxic gas removal by increasing the mixing and reaction efficiency of toxic gas and high-pressure water vapor. . The present invention includes a metal acid treatment chamber (A) connected to one side of a transfer pipe for discharging toxic gas; A first boiler (B) that supplies high-pressure water vapor to a transfer pipe that discharges toxic gas from the metal acid treatment chamber (A); a second boiler (C) connected to a transfer pipe discharging toxic gas from the metal acid treatment chamber (A) and mixing toxic gas and high-pressure water vapor at high temperature; A cyclone (D1) to which the mixed gas of the toxic gas and high-pressure water vapor is supplied, a funnel-shaped inductor (D2) extending concentrically to the lower part of the cyclone (D1), and a valve mounted on the lower part of the inductor (D2) (D3), and a reaction tower (D) including a primary waste liquid collection container (D4) located below the valve (D3) to collect the primary waste liquid; A heat exchange chamber (E1) including a heat exchanger arranged in a concentric circle, extending concentrically to the lower part of the heat exchange chamber (E1), and a transfer pipe through which unreacted toxic gas is supplied from the cyclone (D1) is formed on the inclined surface ( A funnel-shaped inductor (E2) connected to E2'), a valve (E3) mounted on the lower part of the inductor (E2), and a secondary waste liquid collection container located at the lower part of the valve (E3) for collecting secondary waste liquid. Cooling tower (E) including (E4); and a blower (F) connected to a transfer pipe extending from the upper center of the cooling tower (E) to discharge purified air from which toxic gases have been removed.

Description

Device for removing toxic gas generated during metal acid treatment and method for removing toxic gas using the device {TOXIC GAS OBTAINED BY METAL ACID TREATMENT REMOVAL DEVICE AND METHOD OF THE TOXIC GAS USING THE DEVICE}

The present invention relates to a device for removing toxic gases generated during metal acid treatment and a method for removing toxic gases using the device. More specifically, when dissolving metals with strong acids (nitric acid, hydrochloric acid, aqua regia, hydrofluoric acid, etc.) for metal purification, alloy separation, and recovery of metals used in PCBs, including precious metals such as gold, silver, platinum, and palladium. It relates to a device for removing toxic gases such as nitric acid gas and chlorine gas and a method for removing toxic gases using the same.

Conventional cleaning dust collection facilities (scrubbers) installed in accordance with the Air Quality Act are facilities developed to prevent air pollution by treating waste gases generated from discharge facilities, but they are very old-style facilities that were developed before the Environmental Act was enforced, and are used to reduce air pollution. There are many problems, including low pollution prevention and treatment efficiency, high operating costs, and occupying a large space.

Looking specifically at the method of treating waste gas with existing facilities, the waste gas generated from the discharge facility is sucked in by a fan and forced out. A scrubber device is installed on the pipe passing at a speed of 30 to 40 km per hour to allow the waste gas to pass through. This is a method of purification by spraying water from the upper part of the scrubber while the waste gas passes through, allowing the water to come into contact with the waste gas.

However, this method has the disadvantage that a large amount of waste gas cannot be dissolved due to the short contact time between waste gas and water and the small surface area where waste gas contacts water. Therefore, there is no major problem when processing a small amount of waste gas, but when processing a large amount of waste gas in an actual field, a problem arises in which the allowable emission standards cannot be met.

Looking at the prior art shown in the Korean Registered Patent Publication as the first prior art, the Registered Patent Publication (Registration No. 10-1574974: 2015.12.08) discloses a technology related to a harmful gas and complex odor removal system, and a gas treatment tank. (100); One or more packing layers (200) located longitudinally in the gas processing tank; a noxious gas supply unit 300 for supplying noxious odor gas to the bottom of the gas treatment tank; a treated water discharge unit 500 installed at the bottom of the gas tank to discharge treated water from the inside of the gas tank; A harmful gas and complex odor removal system is disclosed, comprising an underwater discharge device that introduces treated water discharged through the treated water discharge unit and generates plasma in the introduced treated water, and the treated water includes porous inorganic particles. there is.

In the harmful gas and complex odor removal system, treated water containing porous inorganic particles with increased adsorption capacity is supplied to the treatment spray pipe 420 through the treated water supply pipe 410 and sprayed onto the three-stage packing layer through a nozzle. In the lower part of the gas treatment tank 100, the harmful odor gas passes through a three-stage packing layer, and the harmful gas and odor components are absorbed or cleaned in the sprayed treated water, and the purified air is discharged to the top of the gas treatment tank. Next, there is no significant difference from the scrubber facility except that instead of water, treated water containing porous inorganic particles that have increased adsorption during the process of passing through the underwater capillary plasma device is used.

As a second prior art, the invention related to 'a wet scrubber using eddy currents and a method of removing harmful gases using the scrubber' is disclosed in the Domestic Patent Publication (Registration No. 10-1740311: 2017.06.08), and more specifically, the invention related to the enclosure A port 111 through which harmful gas is injected is provided on one side, an opening 113 for installing a nozzle 141 is formed on one side of the upper side, and the inside of the enclosure is divided into a plurality of compartments, the bottom of which is a cleaning solution contained inside. A chamber 110 including at least one diaphragm 117 installed to be spaced apart from the water surface; a water supply unit 130 that supplies cleaning liquid so that the cleaning liquid is sprayed from the nozzle 141; and a discharge unit 150 installed on the other side of the chamber 110 and provided with a port 150 to discharge the gas purified from the chamber. A wet scrubber using a vortex is disclosed. The wet scrubber simply absorbs and cleans toxic gases passing below with a cleaning liquid that is sprayed from a nozzle, and the contact time between gas and water is short and the contact surface area is small, so it is difficult to expect high harmful gas cleaning efficiency.

As the third prior art, the Domestic Registered Patent Publication (registration number 10-1609361: 2016.04.21) relates to 'a device for removing harmful gases and dust generated during metal surface treatment', and the inlet (100) through which harmful gases and dust flows. is provided on one side, and a partition plate 110 is formed on the inside parallel to the inlet. A through hole 111 is drilled in the center of the partition plate, and a plurality of inflows are formed on the outer periphery at the top of the partition plate 110. An upper, lower, and lower inductor 120 in the shape of a hopper with a hole 121 perforated is formed. A first spray nozzle 130 is provided on the upper side of the inductor, and the through hole 111 is provided at the bottom of the inductor. A first removal unit (10) through which the penetrating guide tube (140) is coupled to the lower end of the guide body; It is provided at the bottom of the first removal unit 10 and injects the chemical into the first injection nozzle 130 through the first transfer pipe 210 by the first pump 200 provided outside one side. First chemical storage tank (20); A scrubber 300 is provided on the upper side of the induction pipe 140 in a state where one side is perforated to allow inflow, and a second injection nozzle 310 is provided on the upper side of the scrubber, and the second injection nozzle 310 A second removal unit 30 equipped with a demister 320, which is a collision adhesive filter, on the upper side and an outlet 330 on the upper side; and a second chemical storage tank provided at the bottom of the second removal unit and spraying the chemical to the second injection nozzle through the second transfer pipe 410 by the second pump 400 provided outside one side. (40) A device for removing harmful gases and dust generated during metal surface treatment is disclosed.

Looking at the function and operation of the above invention, when reduced pressure is formed in the device by a fan installed at the outlet, harmful gases (nitric acid gas, sulfuric acid gas, chlorine, dust) enter the inlet 100 and perforate the hopper derivative. As it enters the inside of the inductor through the inlet hole, the chemical solution (alkaline aqueous solution such as calcium hydroxide, sodium hydroxide, potassium hydroxide, and sodium carbonate) is sprayed from above through the nozzle 130, and the harmful gas is adsorbed or dissolved in the chemical solution and becomes the first agent. The harmful gases and air that are removed from the rejection and a significant amount of them enter through the inclined surface of the guide pipe, rise, and pass through a scrubber with a large contact surface with the chemical liquid injected from the second chemical tank and sprayed through the second spray nozzle. By doing so, the residual gas is again adsorbed or dissolved in the chemical solution and is removed from the second removal unit, and the air from which the toxic gas has been removed is discharged through the outlet.

The purpose of the above invention is to remove acidic toxic gases generated by using inorganic acids such as nitric acid, hydrochloric acid, and sulfuric acid as a metal treatment. This can be said to have the same purpose as the applied invention, but this applied invention does not use an aqueous alkaline solution and does not use high pressure. It can be said to be characterized by the use of water vapor, and as in the third prior art, a strong alkaline aqueous solution is used, or in the first prior art, porous inorganic particles such as silicon dioxide, alumina, calcium oxide, iron oxide, titanium oxide, dolmite, and silver oxide are used. When chromium oxide, cobalt oxide, etc. are used with treated water, or when a cleaning solution containing microorganisms is used as in the second prior art, expensive chemicals are used, which increases the cost of toxic gas treatment and can cause water pollution. There is a possibility.

Additionally, in order to solve this problem, the present inventor developed a device for removing toxic gases generated during metal acid treatment (Patent Application No. 10-2020-0122703). However, the removal device receives high-pressure steam from the electric steam boiler (B1) in the transfer pipe from the metal acid treatment chamber (A) to the reaction tower (C) and mixes it with toxic gas. The temperature of the high-pressure steam in the transfer pipe is Because it falls very rapidly and a significant portion of the water vapor becomes water, there was a problem of low mixing efficiency of high-pressure water vapor and toxic gas in the reaction tower.

The present invention solves the problems of existing technology and improves the removal device developed by the present inventor by installing an additional boiler to improve the efficiency of toxic gas removal by increasing the mixing and reaction efficiency of toxic gas and high-pressure water vapor. .

In addition, the present invention increases the toxic gas treatment capacity while minimizing the installation equipment of the toxic gas removal device, and also recycles the acid waste liquid obtained by using only high-pressure steam of purified water for metal acid treatment without using chemicals, thereby reducing costs and providing excellent quality. To secure competitiveness.

The present invention includes a metal acid treatment chamber (A) connected to one side of a transfer pipe for discharging toxic gas; A first boiler (B) that supplies high-pressure water vapor to a transfer pipe that discharges toxic gas from the metal acid treatment chamber (A); a second boiler (C) connected to a transfer pipe discharging toxic gas from the metal acid treatment chamber (A) and mixing toxic gas and high-pressure water vapor at high temperature; A cyclone (D1) to which the mixed gas of the toxic gas and high-pressure water vapor is supplied, a funnel-shaped inductor (D2) extending concentrically to the lower part of the cyclone (D1), and a valve mounted on the lower part of the inductor (D2) (D3), and a reaction tower (D) including a primary waste liquid collection container (D4) located below the valve (D3) to collect the primary waste liquid; A heat exchange chamber (E1) including a heat exchanger arranged in a concentric circle, extending concentrically to the lower part of the heat exchange chamber (E1), and a transfer pipe through which unreacted toxic gas is supplied from the cyclone (D1) is formed on the inclined surface ( A funnel-shaped inductor (E2) connected to E2'), a valve (E3) mounted on the lower part of the inductor (E2), and a secondary waste liquid collection container located at the lower part of the valve (E3) for collecting secondary waste liquid. Cooling tower (E) including (E4); and a blower (F) connected to a transfer pipe extending from the upper center of the cooling tower (E) to discharge purified air from which toxic gases have been removed.

The present invention also provides a method for removing toxic gas using the above device, comprising the steps of dissolving metal with strong acid in a metal acid treatment chamber (A) to generate toxic gas; supplying high-pressure water vapor to a transfer pipe discharging toxic gas from the metal acid treatment chamber (A); mixing toxic gas and high-pressure water vapor at high temperature; Recovering the mixed gas of toxic gas and high-pressure water vapor as a primary waste liquid by increasing the mixing speed in the cyclone (D1) of the reaction tower (D) to proceed with dissolution and condensation reactions; Condensing the mixed gas of unreacted toxic gas and high-pressure water vapor through the heat exchange chamber (E1) of the cooling tower (E) to recover the toxic gas as a dissolved secondary waste liquid; and discharging purified air from which toxic gases have been removed through a blower (F).

According to the present invention, the adsorption surface for toxic gases can be maximized by contacting the toxic gases generated during acid treatment with high-pressure water vapor, thereby adsorbing and dissolving a large amount of toxic gases in a short period of time, dramatically increasing the amount of toxic gases processed per hour. It can be increased.

According to the present invention, the mixing efficiency of high-pressure water vapor and toxic gas can be maximized by additionally providing a steam boiler for mixing high-pressure water vapor and toxic gas.

In addition, as in conventional scrubber facilities, porous minerals or alkaline aqueous solutions such as calcium hydroxide, caustic soda, and soda are not used as cleaning solutions, but high-pressure water vapor is used as a reactant to adsorb and dissolve toxic gases, so the treated waste liquid that adsorbs and dissolves toxic gases As a result, a pure strong acid aqueous solution can be obtained, and this aqueous solution can be reused for metal acid treatment, which not only greatly reduces the use of expensive inorganic acids, but also does not cause secondary pollution, giving it a strong competitive edge in field application. .

Figure 1 is a diagram showing a conventionally used toxic gas removal device.
Figure 2 is a diagram showing the toxic gas removal device of the present invention.

Hereinafter, the toxic gas removal device generated during metal acid treatment and the removal method using the device will be described in detail as follows.

The present invention includes a metal acid treatment chamber (A) connected to one side of a transfer pipe for discharging toxic gas; A first boiler (B) that supplies high-pressure water vapor to a transfer pipe that discharges toxic gas from the metal acid treatment chamber (A); a second boiler (C) connected to a transfer pipe discharging toxic gas from the metal acid treatment chamber (A) and mixing toxic gas and high-pressure water vapor at high temperature; A cyclone (D1) to which the mixed gas of the toxic gas and the high-pressure water vapor is supplied, a funnel-shaped inductor (D2) extending concentrically to the lower part of the cyclone (D1), and mounted on the lower part of the inductor (D2) A reaction tower (D) including a valve (D3) and a primary waste liquid collection container (D4) located below the valve (D3) to collect the primary waste liquid; A heat exchange chamber (E1) including a heat exchanger arranged in a concentric circle, extending concentrically to the lower part of the heat exchange chamber (E1), and a transfer pipe through which unreacted toxic gas is supplied from the cyclone (D1) is formed on the inclined surface ( A funnel-shaped inductor (E2) connected to E2'), a valve (E3) mounted on the lower part of the inductor (E2), and a secondary waste liquid collection container located at the lower part of the valve (E3) for collecting secondary waste liquid. Cooling tower (E) including (E4); and a blower (F) connected to a transfer pipe extending from the upper center of the cooling tower (E) to discharge purified air from which toxic gases have been removed.

The second boiler (C) mixes toxic gas and high-pressure water vapor at a temperature of 150°C to 200°C, and the cyclone (D1) is supplied with a mixed gas of toxic gas and high-pressure water vapor at a temperature of 150°C to 200°C.

Here, the primary waste liquid and secondary waste liquid are acidic aqueous solutions.

The present invention also provides a method for removing toxic gas using the above device, comprising the steps of dissolving metal with strong acid in a metal acid treatment chamber (A) to generate toxic gas; supplying high-pressure water vapor to a transfer pipe discharging toxic gas from the metal acid treatment chamber (A); mixing toxic gas and high-pressure water vapor at high temperature; Recovering the mixed gas of toxic gas and high-pressure water vapor as a primary waste liquid by increasing the mixing speed in the cyclone (D1) of the reaction tower (D) to proceed with dissolution and condensation reactions; Condensing the mixed gas of unreacted toxic gas and high-pressure water vapor through the heat exchange chamber (E1) of the cooling tower (E) to recover the toxic gas as a dissolved secondary waste liquid; and discharging purified air from which toxic gases have been removed through a blower (F).

The step of mixing the toxic gas and high-pressure water vapor at high temperature and transferring them to the reaction tower is performed at 150°C to 200°C.

The metals used in the metal acid treatment room (A) are mainly precious metals such as gold, silver, platinum and palladium and their alloys, and the purpose of acid treatment is to improve the purity of precious metals, separate alloys, purify the metal surface, The recovery of metals used in various battery products varies, and the acids used are strong acids such as nitric acid, hydrochloric acid, and aqua regia, and the amount used varies depending on the metal, and is usually used in an amount slightly larger than the equivalent amount. For example, to dissolve 1kg of nitric acid, 1L of water is added to 2L of nitric acid and treated with a diluted aqueous nitric acid solution. The temperature of the metal acid treatment room is 70~80℃, and the temperature of the toxic gas produced is 40~50℃.

A structural feature of the toxic gas removal device of the present invention is that high-pressure water vapor is supplied from the first boiler (B) to the toxic gas formed in the metal acid treatment chamber (A), and the toxic gas and high pressure are heated at high temperature in the second boiler (C). Water vapor mixes. In the case where the second boiler (C) is not present, the high-pressure water vapor supplied from the first boiler (B) rapidly decreases in temperature within the transfer pipe due to the relatively low toxic gas temperature and rapid expansion, causing water to accumulate in the transfer pipe. Therefore, the mixing efficiency of the toxic gas and high-pressure water vapor is poor, and they are transported to the cyclone (D1) in an insufficiently mixed state, thereby lowering the adsorption and dissolution efficiency. By the second boiler, toxic gas and high-pressure water vapor are mixed at a high temperature of 150℃~200℃, and are transported at a high temperature of 150℃~200℃ to the cyclone (D1), where they react at a high speed. This shortens the adsorption and dissolution time of toxic gases, thereby improving the processing ability of toxic gases, thereby achieving miniaturization of the device and cost reduction. When toxic gas and high-pressure water vapor are mixed below 150°C, the probability that the high-pressure water vapor becomes water increases, which reduces mixing efficiency, and mixing above 200°C consumes a lot of energy unnecessarily.

Inside the second boiler, heating tubes are formed concentrically from the bottom to the top of the boiler so that high-pressure water vapor and toxic gas can be well mixed at high temperature.

The first boiler and the second boiler may each be selected from an electric boiler and an oil boiler, and it is preferable that the first boiler is an electric boiler and the second boiler is an oil boiler.

When looking at the surface area of water and water vapor, if water droplets (water droplets), which are spherical bodies with a certain diameter, are subdivided into water droplets with a diameter reduced to 1/10, the surface area of the sum of the subdivided water droplets is 10 times that of the water droplets with the above constant diameter. If the contact surface can be obtained and the water droplets with the above-mentioned constant diameter are subdivided into water droplets with a direct hit of 1/100, the surface area of the sum of the subdivided water droplets can obtain a contact surface 100 times that of the above-mentioned constant diameter water droplets. In other words, theoretically, the scrubber It can be said to be the surface area of a single water droplet falling through a nozzle in a facility and the surface area expressed as the 'surface area of water vapor particles Х number of water vapor particles' made from this single water droplet, so it can be seen that an enormous contact or reaction surface can be provided. .

In order to examine the functions and effects of the device of the present invention listed above, the toxic gas removal device of the present invention is compared with a conventional toxic gas removal device (a device used by our company, hereinafter referred to as a scrubber device).

As shown in Figure 1, the conventional toxic gas removal device (so-called scrubber equipment) currently owned by Sammi Metal allows toxic gas generated in the metal acid treatment chamber (1) to pass through the toxic gas transfer pipe (2) to the blower (3). It enters below the first cleaning tower (S) and rises, passes through the cleaning solution supply pipe (5) by the chemical pump (4), and passes through the two-stage scrubber layer (7), where the cleaning solution is sprayed through the nozzle (6), and is absorbed. , the dissolved and unreacted toxic gas enters under the second washing tower (S') through the unreacted transfer pipe connected to the outlet (8), and passes through the same path as the first washing tower (S), where the toxic gas is removed and washed. It is a toxic gas removal device that discharges the contaminated air through the outlet.

Example (1)

ㆍImplementation device: Toxic gas removal device of the present invention (Figure 2)

ㆍSpecification: Reaction tower cyclone (600ϕ, 60mm)

Cooling tower (1200ϕ, 2000mm)

Electric steam boiler (1st boiler) 30KW

Oil boiler (2nd boiler) 600L

The nitric acid aqueous solution diluted by adding 50 L of water to 100 L of 68% nitric acid was placed in a non-corrosive container, placed in a metal acid treatment room, heated, and maintained at 70°C. Then, 50 kg of copper alloy with a silver content of 70% was placed in a short period of 8 hours. The alloy was added in equal portions at 10-minute intervals and up to 1-hour intervals, and when the metal was dissolved, toxic gases such as nitrogen oxides (NOx) were generated, and the generated toxic gases were removed for 8 hours to end the process. The toxic gas generated in the metal acid treatment room mixes with air and flows into the transfer pipe at a temperature of less than 50℃.

The amount of waste liquid (nitric acid aqueous solution) recovered from the primary waste liquid container in the reaction tower of this device is 41L, with a nitric acid content of 56%, and the amount of waste liquid recovered from the secondary waste liquid container is 110L, with a nitric acid content of 42%, and 8 times per hour. The toxic gas removal rates performed twice are shown in Table 1 below.

Comparative example

ㆍImplementation device: Existing removal device (Figure 1)

ㆍSpecification: 120m ³ 2 scrubbers (1500ϕ, 6000mm, 2 5HP motors)

Add 10 L of water to 20 L of 68% nitric acid and place the diluted nitric acid solution in a non-eroding reaction tank, place it in a metal acid treatment chamber, heat it and maintain it at 70°C, and then add 10 kg of copper alloy with 70% silver content over 8 hours for as little as 10 ℃. When the alloy is added at intervals of minutes or up to an hour and the metal is dissolved, nitrogen oxides begin to be generated and toxic gases are removed at the same level. The results of measuring the toxic gas removal rate eight times per hour are shown below. It is shown in Table 2.

The toxic gas removal work performed with the scrubber cleaning device was carried out in accordance with the Environmental Standards Act. In the method of the comparative example, caustic soda was periodically added to the scrubber, so wastewater was generated and the wastewater had to be neutralized and discharged.

As shown in the above examples, the toxic gas removal device of the present invention has a processing capacity 5 times that of the existing toxic gas removal device (existing harmful gas cleaning device) in the comparative example in the same time (8 hours) and the actual space occupied is It occupies about 1/3 of the conventional device, the capacity (volume) is about 1/5 of that of the existing device, the toxic gas removal rate of the existing device is 90.7%, and the device of the present invention is 98.7%, which is 98.7% of the existing device. It is a toxic gas removal device that greatly exceeds the

A: Metal acid treatment chamber B: First boiler C: Second boiler D: Reaction tower D1: Cyclone D2: Funnel-type inductor D3: Valve D4: Primary waste liquid collection vessel E: Cooling tower E1: Heat exchange chamber E2: Funnel-type inductor E2': Slope E3: Valve E4: Secondary waste liquid collection container F: Blower

Claims (5)

A metal acid treatment room (A) connected to one side with a transfer pipe discharging toxic gas;
A first boiler (B) that supplies high-pressure water vapor to a transfer pipe that discharges toxic gas from the metal acid treatment chamber (A);
a second boiler (C) connected to a transfer pipe discharging toxic gas from the metal acid treatment chamber (A) and mixing toxic gas and high-pressure water vapor at high temperature;
A cyclone (D1) to which the mixed gas of the toxic gas and the high-pressure water vapor is supplied, a funnel-shaped inductor (D2) extending concentrically to the lower part of the cyclone (D1), and mounted on the lower part of the inductor (D2) A reaction tower (D) including a valve (D3) and a primary waste liquid collection container (D4) located below the valve (D3) to collect the primary waste liquid;
A heat exchange chamber (E1) including a heat exchanger arranged in a concentric circle, extending concentrically to the lower part of the heat exchange chamber (E1), and a transfer pipe through which unreacted toxic gas is supplied from the cyclone (D1) is formed on the inclined surface ( A funnel-shaped inductor (E2) connected to E2'), a valve (E3) mounted on the lower part of the inductor (E2), and a secondary waste liquid collection container located at the lower part of the valve (E3) for collecting secondary waste liquid. Cooling tower (E) including (E4); and
A device for removing toxic gases generated during metal acid treatment, including a blower (F) connected to a transfer pipe extending from the upper center of the cooling tower (E) and discharging purified air from which toxic gases have been removed. According to claim 1,
The second boiler (C) mixes toxic gas and high-pressure water vapor at a temperature of 150°C to 200°C, and the cyclone (D1) supplies a mixed gas of toxic gas and high-pressure water vapor at a temperature of 150°C to 200°C. Degassing device. The method of claim 1 or 2,
The first boiler and the second boiler are each selected from an electric boiler and an oil boiler. delete delete