A device for preparing hydrogen fluoride tail gas absorption

Abstract

The present invention discloses a hydrogen fluoride tail gas absorption device, which relates to the technical field of tail gas treatment. The device comprises a sulfuric acid scrubber, a first alkali liquid scrubber, and a second alkali liquid scrubber. A suction pump is connected between the first and second alkali liquid scrubbers. The bottom liquid of the second alkali liquid scrubber serves as the top absorption liquid of the first alkali liquid scrubber. The bottom of the first alkali liquid scrubber is connected to a potassium fluorosilicate preparation chamber, which is connected to an alkali liquid regeneration chamber. The alkali liquid in the alkali liquid regeneration chamber serves as the absorption liquid of the second alkali liquid scrubber. The device treats hydrogen fluoride tail gas through the sulfuric acid scrubber, the first alkali liquid scrubber, and the second alkali liquid scrubber, so that the tail gas meets emission standards. The device is low in cost and high in efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of tail gas treatment, in particular to a tail gas absorption device for preparing hydrogen fluoride. Background Art

[0002] Hydrofluoric acid (HF) is a colorless aqueous solution of hydrogen fluoride gas with a pungent odor. It is highly corrosive and is obtained by dissolving hydrogen fluoride in water. During the hydrogen fluoride production process, non-condensable gases and a small amount of HF are released into the ambient air as tail gases at room temperature. These gases are environmental pollutants and pose occupational health risks. Therefore, these tail gases should be recovered and treated for environmental reasons before being released.

[0003] Patent application number CN201910041562.3 discloses a tail gas absorption device for preparing hydrogen fluoride. The device includes a packed absorption tower, an ammonia spray washing packed tower, and an alkali spray washing packed tower. The tail gas is sequentially treated by the packed absorption tower, the ammonia spray washing packed tower, and the alkali spray washing packed tower before being discharged into the ambient air. The alkali spray washing packed tower of this device uses a NaOH solution as the alkaline washing liquid. After dilution, it is directly injected into the alkaline washing tank or desulfurization tower for desulfurization, producing Na2SO3, Na2SO4, NaHSO3, and NaHSO4. Currently, this tail gas treatment process has the following drawbacks: the use of industrial liquid alkali is large and costly; it generates a large amount of wastewater, which is difficult to treat (the replaced washing liquid is neutral and contains a large amount of NaF, in which the F ions are difficult to treat), and the cost of wastewater treatment is high.

[0004] Therefore, it is of great significance to develop a hydrogen fluoride tail gas absorption device that can be operated and recovered at low operating costs. Summary of the Invention

[0005] The present invention aims to provide a tail gas absorption device for preparing hydrogen fluoride, so as to solve the problems of large amount of industrial liquid alkali used, high cost and large amount of sewage generated.

[0006] In order to achieve the above-mentioned object, the basic scheme of the present invention is as follows: a device for preparing hydrogen fluoride tail gas absorption comprises a sulfuric acid washing tower, a first alkali liquid washing tower and a second alkali liquid washing tower, a suction pump is connected between the first alkali liquid washing tower and the second alkali liquid washing tower, the bottom liquid of the second alkali liquid washing tower is used as the top absorption liquid of the first alkali liquid washing tower, the bottom of the first alkali liquid washing tower is connected to a potassium fluorosilicate preparation chamber, the potassium fluorosilicate preparation chamber is connected to an alkali liquid regeneration chamber, and the alkali liquid in the alkali liquid regeneration chamber is used as the absorption liquid of the second alkali liquid washing tower.

[0007] Furthermore, a first tail gas inlet is provided at the lower portion of one side wall of the sulfuric acid washing tower, a first sulfuric acid atomizer and a second sulfuric acid atomizer are installed on the side wall of the sulfuric acid washing tower, the second sulfuric acid atomizer is located above the first sulfuric acid atomizer, and a plurality of atomizing nozzles are installed on the first sulfuric acid atomizer and the second sulfuric acid atomizer. A sulfuric acid waste liquid recovery bottom is provided at the bottom of the sulfuric acid washing tower, the sulfuric acid waste liquid recovery bottom is connected to a recovery pipe, the recovery pipe is connected to a sulfuric acid waste liquid collection chamber, a first tail gas outlet is provided at the upper portion of the sulfuric acid washing tower, and the first tail gas outlet is connected to a delivery pipe.

[0008] Furthermore, a second tail gas inlet is provided at the lower part of one side wall of the first alkali liquid washing tower, a first water curtain sputterer and a second water curtain sputterer are installed inside the first alkali liquid washing tower, the second water curtain sputterer is located above the first water curtain sputterer, a number of staggered arc blocks are provided on the inner wall of the first alkali liquid washing tower, an arc groove is provided on the arc block, an alkali liquid collecting bottom is provided at the bottom of the first alkali liquid washing tower, the alkali liquid collecting bottom is connected to the potassium fluorosilicate preparation chamber, and a second tail gas outlet is provided at the upper part of the first alkali liquid washing tower.

[0009] Furthermore, a third tail gas inlet is provided at the lower part of one side wall of the second alkali liquid washing tower, a third water curtain splasher and a fourth water curtain splasher are provided on the side wall inside the second alkali liquid washing tower, the fourth water curtain splasher is located above the third water curtain splasher, a number of staggered arc blocks are provided on the inner wall of the second alkali liquid washing tower, an alkali liquid collecting bottom is provided at the bottom of the second alkali liquid washing tower, the alkali liquid collecting bottom is connected to the suction pump, the suction pump is respectively connected to the first water curtain splasher and the second water curtain splasher, and a third tail gas outlet is provided at the upper part of the second alkali liquid washing tower.

[0010] Furthermore, flow detectors are installed at the first exhaust gas inlet, the second exhaust gas inlet and the third exhaust gas inlet.

[0011] Furthermore, the invention also includes a controller, which is electrically connected to the first sulfuric acid atomizer, the second sulfuric acid atomizer, the first water curtain sputterer, the second water curtain sputterer, the third water curtain sputterer, the fourth water curtain sputterer and the suction pump.

[0012] Furthermore, a first booster pump is installed on the first water curtain sputterer, and a second booster pump is installed on the second water curtain sputterer.

[0013] Furthermore, the fluorosilicic acid in the waste washing liquid of the potassium fluorosilicate preparation room is neutralized with potassium carbonate or potassium hydroxide, or precipitated with potassium chloride or potassium sulfate to prepare potassium fluorosilicate as a by-product.

[0014] Furthermore, lime milk is used as a secondary reaction solution in the alkali solution regeneration chamber to displace the NaOH in the recovered alkali solution.

[0015] Furthermore, the power of the second sulfuric acid atomizer is smaller than that of the first sulfuric acid atomizer, the power of the second water curtain sputterer is smaller than that of the first water curtain sputterer, and the power of the fourth water curtain sputterer is smaller than that of the third water curtain sputterer.

[0016] Principle of the basic scheme: Fluorite (CaF2) and sulfuric acid (H2SO4) for the preparation of hydrogen fluoride undergo the following main reaction: CaF2+2H2S04→2HF+CaSO4. The products entering the next process stage mainly include heavy components H2SO4 and H2O, and light components SO2, SiF4, CO2, and H2S. By-products include CaSO4, Fe2(SO4)3, and H2SiF6.

[0017] Tail gas generated during the preparation of hydrogen fluoride enters a sulfuric acid washing tower through a first tail gas inlet. Since the first tail gas inlet is located at the lower part of a side wall of the sulfuric acid washing tower, the tail gas moves upward. A sulfuric acid solution is atomized and sprayed downward through a first sulfuric acid atomizer and a second sulfuric acid atomizer installed on the side wall of the sulfuric acid washing tower and a plurality of atomizing nozzles installed on the sulfuric acid atomizers. The sulfuric acid solution is dispersed downward from the upper part of the sulfuric acid washing tower body. After atomization, the sulfuric acid solution is evenly and fully contacted with the tail gas drifting upward. The tail gas undergoes countercurrent mass transfer exchange with the sulfuric acid solution from bottom to top, so that the sulfuric acid solution removes dust, sulfuric acid mist and moisture in the tail gas. After washing, the sulfuric acid solution is collected at the bottom of the sulfuric acid washing tower. The sulfuric acid waste liquid enters a sulfuric acid waste liquid collection chamber through a recovery pipe connected to the bottom of the sulfuric acid waste liquid recovery chamber. After being treated, the sulfuric acid waste liquid is recycled, thereby reducing costs.

[0018] The tail gas washed by the sulfuric acid washing tower enters the first alkali solution washing tower through the second tail gas inlet, and is sprayed in the form of a water curtain by the first water curtain sputterer and the second water curtain sputterer installed in the first alkali solution washing tower. Then, a plurality of arc blocks arranged in right and wrong directions are provided on the inner wall of the first alkali solution washing tower, and the arc blocks are provided with arc grooves, so that the sprayed sodium hydroxide alkaline solution water curtain hits the arc grooves. Since the sodium hydroxide alkaline solution has a certain initial velocity, the sodium hydroxide alkaline solution water curtain rebounds and continues to be ejected to the next arc block, and is rebounded by the arc groove of the arc block again. The successive downward rebounds of the sodium hydroxide alkaline solution water curtain form layers of sodium hydroxide alkaline solution water curtains. Since the initial velocity of the sodium hydroxide alkaline solution water curtain is constant, the kinetic energy is consumed after multiple rebounds. As a result, the sodium hydroxide alkaline solution will fall downward in a scattered manner due to gravity, and fully mix and react with the tail gas floating upward, achieving a sufficient alkali washing effect; the alkaline solution is collected at the bottom of the tower body through the alkali collection bottom provided at the bottom of the first alkali liquid washing tower, and enters the potassium fluorosilicate preparation chamber connected to the alkali liquid collection bottom. Potassium carbonate or potassium hydroxide is added to the potassium fluorosilicate preparation chamber for neutralization, or potassium chloride or potassium sulfate is used for precipitation to produce a by-product of potassium fluorosilicate; the reaction solution in the potassium fluorosilicate preparation chamber enters the alkali liquid regeneration chamber through a pipeline, lime milk is added to the alkali liquid regeneration chamber as a secondary reaction solution, and NaOH in the recovered alkali liquid is replaced. After treatment, the recovered alkali liquid is used as a washing solution for the second alkali liquid washing tower; the tail gas treated with the sodium hydroxide alkaline solution is discharged through a second tail gas outlet provided at the top of the first alkali liquid washing tower;

[0019] The tail gas enters the second alkali liquid washing tower through a third tail gas inlet provided at the lower part of one side wall of the second alkali liquid washing tower, and is subjected to a secondary alkaline solution washing treatment by the same washing principle as the first alkali liquid washing tower through a third water curtain sputterer and a fourth water curtain sputterer distributed up and down on the side wall of the second alkali liquid washing tower and a plurality of arc blocks arranged in symmetrical positions on the inner wall of the second alkali liquid washing tower; the waste sodium hydroxide alkaline solution is collected by an alkali liquid collecting bottom provided at the bottom of the second alkali liquid washing tower, and the first water curtain sputterer and the second water curtain sputterer are connected to each other through a suction pump, and the sodium hydroxide alkaline solution is sucked into the first water curtain sputterer and the second water curtain sputterer, so that the sodium hydroxide alkaline solution is recycled to save resources. As the sodium hydroxide alkaline solution is transported from the second alkali liquid washing tower to the first alkali liquid washing tower, the solution concentration gradually increases to prevent the sodium hydroxide alkaline solution from not fully reacting. The qualified tail gas is discharged out of the device through the third tail gas outlet provided at the upper part of the second alkali liquid washing tower.

[0020] The first sulfuric acid atomizer, the second sulfuric acid atomizer, the first water curtain sputterer, the second water curtain sputterer, the third water curtain sputterer, the fourth water curtain sputterer and the suction pump are electrically connected through the controller of the device, and flow detectors are installed at the first tail gas inlet, the second tail gas inlet and the third tail gas inlet. The flow detectors detect the flow of tail gas passing through the tail gas inlet and send the detected information to the controller. The controller controls the starting state and working power of the first sulfuric acid atomizer, the second sulfuric acid atomizer, the first water curtain sputterer, the second water curtain sputterer, the third water curtain sputterer, the fourth water curtain sputterer and the suction pump respectively according to the received tail gas flow information, so that the device performs corresponding work according to the flow of tail gas, saves electricity resources and chemical resources, and improves efficiency.

[0021] The beneficial effects achieved by the present invention are as follows: the first alkali liquid washing tower and the second alkali liquid washing tower of the device use NaOH solution as the absorption liquid, which is directly pumped into the alkali washing tank or the desulfurization tower for desulfurization after dilution, to produce Na2SO3, Na2SO4, NaHSO3, and NaHSO4. The solubility of these products is greater than that of CaSO3, CaSO4, CaSO3·1 / 2H2O, and CaSO4·1 / 2H2O, and they are not easy to crystallize and produce scale layers, and can more fully absorb the acidic gas in the tail gas alkali washing.

[0022] The device first adds the sodium hydroxide alkaline solution to the second alkali solution washing tower to wash the tail gas in the second alkali solution washing tower. The sodium hydroxide alkaline solution at this time is an initial unsaturated solution and can fully wash and treat the tail gas. The sodium hydroxide alkaline solution collected at the lower part of the second alkali solution washing tower and having washed the tail gas once is transported to the first alkali solution washing tower to wash the tail gas that has only been subjected to sulfuric acid solution atomization spray degradation, so that the sodium hydroxide alkaline solution is reused for a second time, so that the unsaturated part of the sodium hydroxide alkaline solution used for the first time is fully reacted in the tail gas with higher concentration, so that the sodium hydroxide alkaline solution reaches complete saturation, and then the discarded sodium hydroxide alkaline solution is collected for treatment and recycled, so that the device saves resources, reduces costs, reduces consumption, and improves efficiency.

[0023] The hydrogen fluoride tail gas alkaline washing method of the present invention effectively reduces NaOH usage and wastewater generation, significantly lowering raw material and wastewater treatment costs. By reusing and recycling the sodium hydroxide alkaline solution and returning it to the circulation system, zero wastewater discharge is essentially achieved, reducing wastewater treatment costs and creating a green and environmentally friendly process.

[0024] This device detects the flow rate of exhaust gas passing through the exhaust inlet through a flow detector and sends the detected information to a controller. The controller controls the starting status and working power of the first sulfuric acid atomizer, the second sulfuric acid atomizer, the first water curtain sputterer, the second water curtain sputterer, the third water curtain sputterer, the fourth water curtain sputterer and the suction pump respectively according to the received exhaust gas flow rate information, so that the device performs corresponding work according to the flow rate of the exhaust gas, saving electricity and chemical resources, and eliminating the need for manual intervention to control and adjust the power of the equipment, thereby improving the working efficiency of the device.

[0025] The device of the present invention comprehensively utilizes waste liquid, utilizes potassium fluorosilicate to prepare fluorosilicic acid in waste washing liquid, adds potassium carbonate or potassium hydroxide for neutralization, or uses potassium chloride or potassium sulfate for precipitation to prepare by-product potassium fluorosilicate, thereby improving the product value of the entire device and realizing the cyclic comprehensive utilization of solid and liquid wastes.

[0026] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The figure is a schematic diagram of the main structure of a device for preparing hydrogen fluoride tail gas absorption according to the present invention. DETAILED DESCRIPTION

[0028] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0029] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "vertical", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0030] In the description of the present invention, unless otherwise specified and limited, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the internal communication between two components. It can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances.

[0031] The following is further described in detail through specific implementation methods:

[0032] The figure marks in the drawings of the specification include: sulfuric acid washing tower 1, first alkali liquid washing tower 2, second alkali liquid washing tower 3, first tail gas inlet 4, first sulfuric acid atomizer 5, second sulfuric acid atomizer 6, atomizing nozzle 7, sulfuric acid waste liquid recovery bottom 8, recovery pipe 9, sulfuric acid waste liquid collecting chamber 10, first tail gas outlet 11, delivery pipe 12, second tail gas inlet 13, first water curtain sputterer 14, second water curtain sputterer 15, arc block 16, alkali liquid collecting bottom 17, potassium fluorosilicate preparation chamber 18, alkali liquid regeneration chamber 19, second tail gas outlet 20, third tail gas inlet 21, third water curtain sputterer 22, fourth water curtain sputterer 23, flow detector 24, suction pump 25, first booster pump 26, second booster pump 27, third tail gas outlet 28.

[0033] The embodiment is basically as shown in the attached Figure 1 As shown: A device for preparing hydrogen fluoride tail gas absorption, comprising a sulfuric acid washing tower 1, a first alkali liquid washing tower 2 and a second alkali liquid washing tower 3, a suction pump 25 is connected between the first alkali liquid washing tower 2 and the second alkali liquid washing tower 3, the bottom liquid of the second alkali liquid washing tower 3 is used as the top absorption liquid of the first alkali liquid washing tower 2, the bottom of the first alkali liquid washing tower 2 is connected to a potassium fluorosilicate preparation chamber 18, the potassium fluorosilicate preparation chamber 18 is connected to an alkali liquid regeneration chamber 19, and the alkali liquid in the alkali liquid regeneration chamber 19 is used as the absorption liquid of the second alkali liquid washing tower 3.

[0034] As attached Figure 1 As shown: the lower part of one side wall of the sulfuric acid washing tower 1 is connected to a first tail gas inlet 4, the side wall of the sulfuric acid washing tower 1 is installed with a first sulfuric acid atomizer 5 and a second sulfuric acid atomizer 6, the second sulfuric acid atomizer 6 is located above the first sulfuric acid atomizer 5, and the first sulfuric acid atomizer 5 and the second sulfuric acid atomizer 6 are both installed with a plurality of atomizing nozzles 7, the bottom of the sulfuric acid washing tower 1 is provided with a sulfuric acid waste liquid recovery bottom 8, the sulfuric acid waste liquid recovery bottom 8 is connected to a recovery pipe 9, the recovery pipe 9 is connected to a sulfuric acid waste liquid collection chamber 10, the upper part of the sulfuric acid washing tower 1 is connected to a first tail gas outlet 11, and the first tail gas outlet 11 is connected to a delivery pipe 12.

[0035] As attached Figure 1 As shown: the lower part of one side wall of the first alkali liquid washing tower 2 is connected to the second tail gas inlet 13, the first alkali liquid washing tower 2 is equipped with a first water curtain sputterer 14 and a second water curtain sputterer 15, the second water curtain sputterer 15 is located above the first water curtain sputterer 14, a plurality of staggered arc blocks 16 are fixedly connected to the inner wall of the first alkali liquid washing tower 2, and an arc groove is processed on the arc block 16, an alkali liquid collecting bottom 17 is installed at the bottom of the first alkali liquid washing tower 2, the alkali liquid collecting bottom 17 is connected to the potassium fluorosilicate preparation chamber 18, and the upper part of the first alkali liquid washing tower 2 is connected to the second tail gas outlet 20.

[0036] As attached Figure 1 As shown: the lower part of one side wall of the second alkali liquid washing tower 3 is connected to the third tail gas inlet 21, the side wall inside the second alkali liquid washing tower 3 is installed with a third water curtain splasher 22 and a fourth water curtain splasher 23, the fourth water curtain splasher 23 is located above the third water curtain splasher 22, and a plurality of staggered arc blocks 16 are fixedly connected to the inner wall of the second alkali liquid washing tower 3. The alkali liquid collecting bottom 17 is installed at the bottom of the second alkali liquid washing tower 3. The alkali liquid collecting bottom 17 is connected to the suction pump 25, and the suction pump 25 is respectively connected to the first water curtain splasher 14 and the second water curtain splasher 15. The upper part of the second alkali liquid washing tower 3 is connected to the third tail gas outlet 28.

[0037] As attached Figure 1 As shown, flow detectors 24 are installed at the first exhaust gas inlet 4 , the second exhaust gas inlet 13 and the third exhaust gas inlet 21 .

[0038] As attached Figure 1 As shown: it also includes a controller, which is electrically connected to the first sulfuric acid atomizer 5, the second sulfuric acid atomizer 6, the first water curtain splasher 14, the second water curtain splasher 15, the third water curtain splasher 22, the fourth water curtain splasher 23 and the suction pump 25.

[0039] As attached Figure 1 As shown, a first booster pump 26 is installed on the first water curtain splasher 14 , and a second booster pump 27 is installed on the second water curtain splasher 15 .

[0040] As attached Figure 1 As shown: The fluorosilicic acid in the waste washing liquid of the potassium fluorosilicate preparation chamber 18 is neutralized with potassium carbonate or potassium hydroxide, or precipitated with potassium chloride or potassium sulfate to produce potassium fluorosilicate as a by-product.

[0041] As attached Figure 1 As shown: lime milk is used as a secondary reaction solution in the alkali solution regeneration chamber 19 to replace the NaOH in the recovered alkali solution.

[0042] As attached Figure 1 As shown, the power of the second sulfuric acid atomizer 6 is less than that of the first sulfuric acid atomizer 5 , the power of the second water curtain sputterer 15 is less than that of the first water curtain sputterer 14 , and the power of the fourth water curtain sputterer 23 is less than that of the third water curtain sputterer 22 .

[0043] The specific implementation process is as follows: Fluorite (CaF2) and sulfuric acid (H2SO4) for preparing hydrogen fluoride undergo the following main reaction: CaF2+2H2S04→2HF+CaSO4. The products entering the next process stage mainly include heavy components H2SO4 and H2O, and light components SO2, SiF4, CO2, and H2S. By-products include CaSO4, Fe2(SO4)3, and H2SiF6.

[0044] The tail gas generated by preparing hydrogen fluoride enters the interior of the sulfuric acid washing tower 1 through the first tail gas inlet 4. Since the first tail gas inlet 4 is at the lower part of the side wall of the sulfuric acid washing tower 1, the tail gas will move upward. The sulfuric acid solution is atomized and sprayed downward by the first sulfuric acid atomizer 5 and the second sulfuric acid atomizer 6 installed on the side wall of the sulfuric acid washing tower 1 and a plurality of atomizing nozzles 7 installed on the sulfuric acid atomizers. The sulfuric acid solution is dispersed downward from the upper part of the tower body of the sulfuric acid washing tower 1. After atomization, the sulfuric acid solution is evenly and fully contacted with the tail gas drifting upward. The tail gas exchanges mass with the sulfuric acid solution from bottom to top in a countercurrent flow manner, so that the sulfuric acid solution removes dust, sulfuric acid mist and moisture in the tail gas. After washing, the sulfuric acid solution is collected at the bottom of the sulfuric acid washing tower 1 and enters the sulfuric acid waste liquid collection chamber 10 through a recovery pipe 9 connected to the sulfuric acid waste liquid recovery bottom 8. After treatment, the sulfuric acid waste liquid is recycled to reduce costs.

[0045] The tail gas washed by the sulfuric acid washing tower 1 enters the first alkali solution washing tower 2 through the second tail gas inlet 13, and is sprayed in the form of a water curtain by the first water curtain sputterer 14 and the second water curtain sputterer 15 installed in the first alkali solution washing tower 2. Then, a plurality of arc blocks 16 arranged in right and wrong directions are provided on the inner wall of the first alkali solution washing tower 2. The arc blocks 16 are provided with arc grooves, so that the sprayed sodium hydroxide alkaline solution water curtain hits the arc grooves. Since the sodium hydroxide alkaline solution has a certain initial speed, the sodium hydroxide alkaline solution water curtain rebounds and continues to be ejected to the next arc block 16, and is once again rebounded by the arc groove of the arc block 16. The successive downward rebounds of the sodium hydroxide alkaline solution water curtain form layers of sodium hydroxide alkaline solution water curtains. Since the initial speed of the sodium hydroxide alkaline solution water curtain is constant, the kinetic energy is consumed after multiple rebounds, thereby hydrogen The sodium oxide alkaline solution will fall downward in a scattered manner due to gravity, and will fully mix and react with the tail gas floating upward, achieving a sufficient alkali washing effect; the alkaline solution is collected at the bottom of the tower body through the alkali collection bottom 17 provided at the bottom of the first alkali solution washing tower 2, and the sodium hydroxide alkaline solution enters the potassium fluorosilicate preparation chamber 18 connected to the alkali solution collection bottom 17, and potassium carbonate or potassium hydroxide is added to the potassium fluorosilicate preparation chamber 18 for neutralization, or potassium chloride or potassium sulfate is used for precipitation to produce a by-product potassium fluorosilicate; the reaction solution in the potassium fluorosilicate preparation chamber 18 enters the alkali solution regeneration chamber 19 through a pipeline, and lime milk is added to the alkali solution regeneration chamber 19 as a secondary reaction solution to replace the NaOH in the recovered alkali solution, and then used as a washing solution for the second alkali solution washing tower 3 after treatment; the tail gas treated with the sodium hydroxide alkaline solution is discharged through the second tail gas outlet 20 provided at the upper part of the first alkali solution washing tower 2;

[0046] The tail gas enters the second alkali liquid washing tower 3 through the third tail gas inlet 21 provided at the lower part of one side wall of the second alkali liquid washing tower 3, and passes through the third water curtain sputterer 22 and the fourth water curtain sputterer 23 provided on the side wall of the second alkali liquid washing tower 3 and the arc blocks 16 provided on the inner wall of the second alkali liquid washing tower 3. Due to the same washing principle as the first alkali liquid washing tower 2, the tail gas is subjected to a secondary alkaline solution washing treatment; the waste sodium hydroxide alkaline solution is collected through the alkali liquid collecting bottom 17 provided at the bottom of the second alkali liquid washing tower 3. The solution is collected and connected to the first water curtain sputterer 14 and the second water curtain sputterer 15 respectively through the suction pump 25, and the sodium hydroxide alkaline solution is sucked into the first water curtain sputterer 14 and the second water curtain sputterer 15. The sodium hydroxide alkaline solution is recycled to save resources. As the sodium hydroxide alkaline solution is transported from the second alkali solution washing tower 3 to the first alkali solution washing tower 2, the solution concentration gradually increases to prevent the sodium hydroxide alkaline solution from not fully reacting. The qualified tail gas is discharged out of the device through the third tail gas outlet 28 provided at the upper part of the second alkali solution washing tower 3.

[0047] The first sulfuric acid atomizer 5, the second sulfuric acid atomizer 6, the first water curtain sputterer 14, the second water curtain sputterer 15, the third water curtain sputterer 22, the fourth water curtain sputterer 23 and the suction pump 25 are electrically connected through the controller of the device, and a flow detector 24 is installed at the first tail gas inlet 4, the second tail gas inlet 13 and the third tail gas inlet 21. The flow detector 24 detects the flow of tail gas passing through the tail gas inlet and sends the detected information to the controller. The controller controls the starting state and working power of the first sulfuric acid atomizer 5, the second sulfuric acid atomizer 6, the first water curtain sputterer 14, the second water curtain sputterer 15, the third water curtain sputterer 22, the fourth water curtain sputterer 23 and the suction pump 25 respectively according to the received tail gas flow information, so that the device performs corresponding work according to the flow of tail gas, saves electricity resources and chemical resources, and improves efficiency.

[0048] The above is only an embodiment of the present invention, and common knowledge such as the specific structure and / or characteristics of the scheme is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A device for absorbing tail gas from hydrogen fluoride, characterized in that: The invention comprises a sulfuric acid washing tower, a first alkali liquid washing tower and a second alkali liquid washing tower, wherein a suction pump is connected between the first alkali liquid washing tower and the second alkali liquid washing tower, the bottom liquid of the second alkali liquid washing tower is used as the top absorption liquid of the first alkali liquid washing tower, the bottom of the first alkali liquid washing tower is connected to a potassium fluorosilicate preparation chamber, the potassium fluorosilicate preparation chamber is connected to an alkali liquid regeneration chamber, and the alkali liquid in the alkali liquid regeneration chamber is used as the absorption liquid of the second alkali liquid washing tower; A first tail gas inlet is provided at the lower portion of one side wall of the sulfuric acid washing tower, a first sulfuric acid atomizer and a second sulfuric acid atomizer are installed on the side wall of the sulfuric acid washing tower, the second sulfuric acid atomizer is located above the first sulfuric acid atomizer, and a plurality of atomizing nozzles are installed on the first sulfuric acid atomizer and the second sulfuric acid atomizer. A sulfuric acid waste liquid recovery bottom is provided at the bottom of the sulfuric acid washing tower, the sulfuric acid waste liquid recovery bottom is connected to a recovery pipe, and the recovery pipe is connected to a sulfuric acid waste liquid collection chamber. A first tail gas outlet is provided at the upper portion of the sulfuric acid washing tower, and the first tail gas outlet is connected to a delivery pipe. A second tail gas inlet is provided at the lower portion of one side wall of the first alkali liquid washing tower, a first water curtain sputterer and a second water curtain sputterer are installed inside the first alkali liquid washing tower, the second water curtain sputterer is located above the first water curtain sputterer, a plurality of arc blocks arranged in a staggered manner are provided on the inner wall of the first alkali liquid washing tower, an arc groove is provided on the arc block, an alkali liquid collecting bottom is provided at the bottom of the first alkali liquid washing tower, the alkali liquid collecting bottom is connected to the potassium fluorosilicate preparation chamber, and a second tail gas outlet is provided at the upper portion of the first alkali liquid washing tower; The power of the second sulfuric acid atomizer is smaller than that of the first sulfuric acid atomizer, the power of the second water curtain sputterer is smaller than that of the first water curtain sputterer, and the power of the fourth water curtain sputterer is smaller than that of the third water curtain sputterer.

2. The tail gas absorption device for preparing hydrogen fluoride according to claim 1, characterized in that: The system also includes a controller, which is electrically connected to the first sulfuric acid atomizer, the second sulfuric acid atomizer, the first water curtain sputterer, the second water curtain sputterer, the third water curtain sputterer, the fourth water curtain sputterer and the suction pump.

3. The tail gas absorption device for preparing hydrogen fluoride according to claim 1, characterized in that: A first booster pump is installed on the first water curtain splasher, and a second booster pump is installed on the second water curtain splasher.

4. The tail gas absorption device for preparing hydrogen fluoride according to claim 1, characterized in that: The fluorosilicic acid in the waste washing liquid of the potassium fluorosilicate preparation room is neutralized with potassium carbonate or potassium hydroxide, or precipitated with potassium chloride or potassium sulfate to produce the by-product potassium fluorosilicate.

5. The tail gas absorption device for preparing hydrogen fluoride according to claim 1, characterized in that: Lime milk is used as the secondary reaction solution in the alkali liquor regeneration chamber to displace the NaOH in the recovered alkali liquor.

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