阅读说明：本技术 一种含氟废液副产氟硅酸的制备方法 (Preparation method of fluosilicic acid byproduct of fluorine-containing waste liquid ) 是由 段伟伟 郭远石 方阔 于 2021-01-13 设计创作，主要内容包括：本发明公开了一种含氟废液副产氟硅酸的制备方法,包括步骤一：将20份的氢氟酸混合液置入蚀刻槽中,将1份玻璃用粉碎机粉碎后置入蚀刻槽中；步骤二：将氢氟酸与玻璃反应生成的气态物质四氟化硅与过量的氢氟酸反应生成氟硅酸；步骤三：将玻璃中的金属氧化物如氧化钠和氧化钙与氟硅酸反应生成氟硅酸盐；步骤四：将一部分氟硅酸通过高温排酸管道和泵机注入副产氟硅酸桶中,将另一部分氟硅酸通过HF回收管注入回收桶中。该含氟废液副产氟硅酸的制备方法,通过设置蚀刻槽、回收桶、压滤后回收桶和副产氟硅酸桶,实现了含氟废液副产氟硅酸的效果,使蚀刻后产生的废液无法得到充分的回收有效利用,降低了资源浪费和较高的处理成本。(The invention discloses a preparation method of fluosilicic acid as a byproduct of fluorine-containing waste liquid, which comprises the following steps: placing 20 parts of hydrofluoric acid mixed solution into an etching tank, and placing 1 part of glass into the etching tank after being crushed by a crusher; step two: reacting gaseous silicon tetrafluoride generated by the reaction of hydrofluoric acid and glass with excessive hydrofluoric acid to generate fluosilicic acid; step three: reacting metal oxides such as sodium oxide and calcium oxide in the glass with fluosilicic acid to generate fluosilicate; step four: injecting one part of fluosilicic acid into a byproduct fluosilicic acid bucket through a high-temperature acid discharge pipeline and a pump machine, and injecting the other part of fluosilicic acid into a recovery bucket through an HF recovery pipe. According to the preparation method of the fluorine-containing waste liquid byproduct fluosilicic acid, the etching tank, the recycling tank, the filter-pressed recycling tank and the byproduct fluosilicic acid tank are arranged, so that the effect of the fluorine-containing waste liquid byproduct fluosilicic acid is realized, the waste liquid generated after etching cannot be fully recycled, and the resource waste and higher treatment cost are reduced.)

1. A preparation method of fluosilicic acid as a byproduct of fluorine-containing waste liquid is characterized by comprising the following steps: the method comprises the following steps:

the method comprises the following steps: placing 20 parts of hydrofluoric acid mixed solution into an etching tank, and placing 1 part of glass into the etching tank after being crushed by a crusher;

step two: reacting gaseous silicon tetrafluoride generated by the reaction of hydrofluoric acid and glass with excessive hydrofluoric acid to generate fluosilicic acid;

step three: reacting metal oxides such as sodium oxide and calcium oxide in the glass with fluosilicic acid to generate fluosilicate;

step four: injecting one part of fluosilicic acid into a by-product fluosilicic acid bucket through a high-temperature acid discharge pipeline and a pump machine, and injecting the other part of fluosilicic acid into a recovery bucket through an HF recovery pipe;

step five: the fluosilicic acid in the recycling barrel is connected into a filter press through an HP filter pressing pipe and a pump machine, and the fluosilicic acid salt is filtered and removed through the filter press to obtain clear liquid HF and H₂SiF₆、H₂O；

Step six: the clear liquid is HF, H₂SiF₆、H₂Injecting O into a recycling bin after filter pressing through a pipeline and a pump;

step seven: the clear liquid is HF, H₂SiF₆、H₂After being subjected to filter pressing, the O is recycled and then is connected into an etching tank through an HF recycling pipe and a pump to react with glass to continuously consume hydrofluoric acid in the O, so that the concentration of fluosilicate is continuously increased;

step eight: injecting the other part of fluosilicate into a by-product fluosilicic acid bucket through a high-temperature acid discharge pipe and a pump machine;

step nine: and injecting the byproduct fluosilicate in the byproduct fluosilicic acid barrel into a filter press through a pipeline and a pump machine, carrying out titration test on the concentration of the fluosilicic acid, and discharging after the concentration reaches the standard.

2. The method for preparing fluosilicic acid as a by-product from a fluorine-containing waste liquid according to claim 1, which is characterized in that: in the first step, 20 parts of hydrofluoric acid mixed solution comprises 50% of hydrofluoric acid, 10 parts of water and 10 parts of hydrofluoric acid, and in the first step, 1 part of glass comprises 80% of SiO₂And 20% of Na₂A mixture of O and CaO.

3. The method for preparing fluosilicic acid as a by-product from a fluorine-containing waste liquid according to claim 1, which is characterized in that: and (3) crushing the glass in the first step into granular glass with the diameter of 0.5-3 mm by using a crusher, wherein a stirring mechanism is fixedly arranged in the etching tank in the first step, and a heating element is fixedly arranged on a stirring blade of the stirring mechanism.

4. The method for preparing fluosilicic acid as a by-product from a fluorine-containing waste liquid according to claim 1, which is characterized in that: in the third step, in the etching reaction process, the amount of hydrofluoric acid is excessive, and the main component in the glass is SiO₂70-80% of metal oxide Na₂The proportion of the mixture of O and CaO is 20-30%, and the etching solution after reaction according to the reaction proportion contains HF and H as main components₂SiF₆Fluorosilicate, H₂O。

5. The method for preparing fluosilicic acid as a by-product from a fluorine-containing waste liquid according to claim 1, which is characterized in that: and C, fixedly arranging a stirring mechanism in the recycling bin in the step four, and fixedly arranging a heating element on a stirring blade of the stirring mechanism.

6. The method for preparing fluosilicic acid as a by-product from a fluorine-containing waste liquid according to claim 1, which is characterized in that: an electric valve is fixedly arranged on the high-temperature acid discharge pipeline in the fourth step; and an electric valve is fixedly arranged on the HF recovery pipeline.

7. The method for preparing fluosilicic acid as a by-product from a fluorine-containing waste liquid according to claim 1, which is characterized in that: and C, fixedly arranging a centrifugal mechanism in the pressure-filtered recovery barrel in the step six, wherein the centrifugal separation time is 1-3h, and the rotating speed of the centrifugal mechanism is 2000-5000 r/min.

8. The method for preparing fluosilicic acid as a by-product from a fluorine-containing waste liquid according to claim 1, which is characterized in that: after 20 parts of hydrofluoric acid mixed solution and 1 part of glass react in the step one, the content of consumed hydrofluoric acid is 6 parts, and 4 parts are remained to generateThe content of the fluosilicic acid is 0.6 part (and 80 percent of SiO)₂Reaction to produce 0.8 portion of fluosilicic acid and 20 percent of (Na)₂O, CaO) consumes 0.2 parts of fluorosilicic acid), with a water content of 11.8 parts water (with 80% SiO)₂Reaction to produce 1.6 parts water, 20% (Na)₂O, CaO) reacting to produce 0.2 part of water), and the generated fluosilicate is 0.2 part; and then uniformly recovering through a recovery barrel, and performing filter pressing through a filter press to remove the fluosilicate in the clear liquid, wherein the mass fraction of the fluosilicic acid in the clear liquid is 21.47 percent ((0.6 x 144)/((0.6 x 144) + (4 x 20) + (11.8 x 20))).

Technical Field

The invention relates to the technical field of fluosilicic acid byproduct in inorganic chemical industry, in particular to a preparation method of fluosilicic acid byproduct in fluorine-containing waste liquid.

Background

The method is mainly used for treating the high-concentration fluorine-containing waste liquid, and adopts a calcium salt precipitation method, namely a lime precipitation method, lime milk is added into the waste liquid until the waste liquid is completely alkaline, the lime precipitation method is mainly used, and the waste liquid is fully stirred and is filtered after being placed for one night.

In a chemical process, waste liquid generated after etching contains multiple substances such as hydrofluoric acid, fluosilicic acid, fluorosilicate and the like, and in the prior art, fluorine-containing waste liquid cannot be subjected to solid-liquid separation from acid liquid, fluorosilicate is removed, the acid liquid cannot be recycled for multiple times and then subjected to solid-liquid separation for multiple times, and the concentration of fluosilicic acid is continuously concentrated through process design to reach a byproduct, so that a preparation method of the fluorine-containing waste liquid byproduct fluosilicic acid is provided.

Disclosure of Invention

The invention aims to provide a preparation method of a fluorine-containing waste liquid byproduct fluosilicic acid, which aims to solve the problems that the fluorine-containing waste liquid in the prior art proposed in the background art can not be subjected to solid-liquid separation from an acid liquid, fluosilicate is removed, the acid liquid can not be recycled for multiple times and then subjected to solid-liquid separation for multiple times, and the concentration of fluosilicic acid is continuously concentrated through process design to reach the byproduct.

In order to achieve the purpose, the invention provides the following technical scheme: a preparation method of fluosilicic acid as a byproduct of fluorine-containing waste liquid comprises the following steps:

the method comprises the following steps: placing 20 parts of hydrofluoric acid mixed solution into an etching tank, and placing 1 part of glass into the etching tank after being crushed by a crusher;

step two: reacting gaseous silicon tetrafluoride generated by the reaction of hydrofluoric acid and glass with excessive hydrofluoric acid to generate fluosilicic acid;

step three: reacting metal oxides such as sodium oxide and calcium oxide in the glass with fluosilicic acid to generate fluosilicate;

step four: injecting one part of fluosilicic acid into a by-product fluosilicic acid bucket through a high-temperature acid discharge pipeline and a pump machine, and injecting the other part of fluosilicic acid into a recovery bucket through an HF recovery pipe;

step five: the fluosilicic acid in the recycling barrel is connected into a filter press through an HP filter pressing pipe and a pump machine, and the fluosilicic acid salt is filtered and removed through the filter press to obtain clear liquid HF and H₂SiF₆、H₂O；

Step six: the clear liquid is HF, H₂SiF₆、H₂Injecting O into a recycling bin after filter pressing through a pipeline and a pump;

step seven: the clear liquid is HF, H₂SiF₆、H₂After being subjected to filter pressing, the O is recycled and then is connected into an etching tank through an HF recycling pipe and a pump to react with glass to continuously consume hydrofluoric acid in the O, so that the concentration of fluosilicate is continuously increased;

step eight: injecting the other part of fluosilicate into a by-product fluosilicic acid bucket through a high-temperature acid discharge pipe and a pump machine;

step nine: and injecting the byproduct fluosilicate in the byproduct fluosilicic acid barrel into a filter press through a pipeline and a pump machine, carrying out titration test on the concentration of the fluosilicic acid, and discharging after the concentration reaches the standard.

Preferably, in the first step, 20 parts of the hydrofluoric acid mixed solution comprises 50% of hydrofluoric acid, 10 parts of water and 10 parts of hydrofluoric acid, and in the first step, 1 part of the glass comprises 80% of SiO₂And 20% of Na₂A mixture of O and CaO.

Preferably, the glass in the first step is crushed into granular glass with the diameter of 0.5-3 mm by a crusher, a stirring mechanism is fixedly arranged in the etching tank in the first step, and a heating element is fixedly arranged on a stirring blade of the stirring mechanism.

Preferably, in the third step, the amount of hydrofluoric acid is excessive during the etching reaction, and the main component in the glass is SiO₂70-80% of metal oxide Na₂The proportion of the mixture of O and CaO is 20-30%, and the etching solution after reaction according to the reaction proportion contains HF and H as main components₂SiF₆Fluorosilicate, H₂O。

Preferably, a stirring mechanism is fixedly arranged in the recycling bin in the fourth step, and a heating element is fixedly arranged on a stirring blade of the stirring mechanism.

Preferably, an electric valve is fixedly arranged on the high-temperature acid discharge pipeline in the fourth step; and an electric valve is fixedly arranged on the HF recovery pipeline.

Preferably, a centrifugal mechanism is fixedly arranged in the pressure-filtered recovery barrel in the sixth step, the centrifugal separation time is 1-3h, and the rotating speed of the centrifugal mechanism is 2000-5000 r/min.

Preferably, after 20 parts of hydrofluoric acid mixed solution and 1 part of glass react in the first step, the content of consumed hydrofluoric acid is 6 parts, and the remaining 4 parts are 0.6 part (of hydrofluoric acid and 80% of SiO) of generated fluosilicic acid₂Reaction to produce 0.8 portion of fluosilicic acid and 20 percent of (Na)₂O, CaO) consumes 0.2 parts of fluorosilicic acid), with a water content of 11.8 parts water (with 80% SiO)₂Reaction to produce 1.6 parts water, 20% (Na)₂O, CaO) reacting to produce 0.2 part of water), and the generated fluosilicate is 0.2 part; and then uniformly recovering through a recovery barrel, and performing filter pressing through a filter press to remove the fluosilicate in the clear liquid, wherein the mass fraction of the fluosilicic acid in the clear liquid is 21.47 percent ((0.6 x 144)/((0.6 x 144) + (4 x 20) + (11.8 x 20))).

Compared with the prior art, the invention has the beneficial effects that:

1. according to the preparation method of the fluorine-containing waste liquid byproduct fluosilicic acid, the etching tank, the recovery barrel after filter pressing and the byproduct fluosilicic acid barrel are arranged, so that the effect of the fluorine-containing waste liquid byproduct fluosilicic acid is realized, the waste liquid generated after etching cannot be fully recovered and effectively utilized, the waste of a large amount of waste liquid treatment cost is effectively avoided, and the resource waste and higher treatment cost are reduced;

2. according to the preparation method of the fluosilicic acid byproduct from the fluorine-containing waste liquid, the stirring mechanism and the heating element are arranged in the recovery barrel, the hydrofluoric acid can be heated, the reaction of the hydrofluoric acid is facilitated, the delivery of the fluosilicic acid solution is facilitated by arranging the electric valve, and the use is convenient;

3. this preparation method of fluoride waste liquid byproduct fluosilicic acid through setting up high temperature acid discharge pipe, has realized carrying out the effect that heats to fluorosilicate at the acid discharge in-process, does benefit to the follow-up reaction of fluorosilicate, through setting up the rubbing crusher, does benefit to smash glass, does benefit to the abundant reaction of glass and solution, has improved the production effect of hydrogen fluoride greatly for going on of reaction has improved production efficiency, convenient to use.

Drawings

FIG. 1 is a flow chart of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, the present invention provides a technical solution: a preparation method of fluosilicic acid as a byproduct of fluorine-containing waste liquid comprises the following steps:

the method comprises the following steps: placing 20 parts of hydrofluoric acid mixed solution into an etching tank, and placing 1 part of glass into the etching tank after being crushed by a crusher;

step two: reacting gaseous silicon tetrafluoride generated by the reaction of hydrofluoric acid and glass with excessive hydrofluoric acid to generate fluosilicic acid;

step three: reacting metal oxides such as sodium oxide and calcium oxide in the glass with fluosilicic acid to generate fluosilicate;

step four: injecting one part of fluosilicic acid into a by-product fluosilicic acid bucket through a high-temperature acid discharge pipeline and a pump machine, and injecting the other part of fluosilicic acid into a recovery bucket through an HF recovery pipe;

step five: the fluosilicic acid in the recycling barrel is connected into a filter press through an HP filter pressing pipe and a pump machine, and the fluosilicic acid salt is filtered and removed through the filter press to obtain clear liquid HF and H₂SiF₆、H₂O；

Step six: the clear liquid is HF, H₂SiF₆、H₂O-channel pipeline and pumpInjecting into a recycling bin after filter pressing;

step seven: the clear liquid is HF, H₂SiF₆、H₂After being subjected to filter pressing, the O is recycled and then is connected into an etching tank through an HF recycling pipe and a pump to react with glass to continuously consume hydrofluoric acid in the O, so that the concentration of fluosilicate is continuously increased;

step eight: injecting the other part of fluosilicate into a by-product fluosilicic acid bucket through a high-temperature acid discharge pipe and a pump machine;

step nine: and injecting the byproduct fluosilicate in the byproduct fluosilicic acid barrel into a filter press through a pipeline and a pump machine, carrying out titration test on the concentration of the fluosilicic acid, and discharging after the concentration reaches the standard.

Further, in the first step, 20 parts of hydrofluoric acid mixed solution comprises 50% of hydrofluoric acid, 10 parts of water and 10 parts of hydrofluoric acid, and in the first step, 1 part of glass comprises 80% of SiO₂And 20% of Na₂A mixture of O and CaO.

Further, the glass in the first step is crushed into granular glass with the diameter of 0.5-3 mm by a crusher, a stirring mechanism is fixedly arranged in the etching tank in the first step, and a heating element is fixedly arranged on a stirring blade of the stirring mechanism.

Furthermore, in the third step, the amount of hydrofluoric acid is excessive during the etching reaction, and the main component in the glass is SiO₂70-80% of metal oxide Na₂The proportion of the mixture of O and CaO is 20-30%, and the etching solution after reaction according to the reaction proportion contains HF and H as main components₂SiF₆Fluorosilicate, H₂O。

Furthermore, a stirring mechanism is fixedly arranged in the recycling bin in the fourth step, and a heating element is fixedly arranged on a stirring blade of the stirring mechanism.

Further, an electric valve is fixedly arranged on the high-temperature acid discharge pipeline in the fourth step; and an electric valve is fixedly arranged on the HF recovery pipeline.

Further, a centrifugal mechanism is fixedly arranged in the recycling bin after filter pressing in the sixth step, the centrifugal separation time is 1-3h, and the rotating speed of the centrifugal mechanism is 2000-5000 r/min.

Further, after 20 parts of hydrofluoric acid mixed solution and 1 part of glass react in the first step, the content of consumed hydrofluoric acid is 6 parts, and the remaining 4 parts are 0.6 part (of hydrofluoric acid and 80% of SiO) are generated₂Reaction to produce 0.8 portion of fluosilicic acid and 20 percent of (Na)₂O, CaO) consumes 0.2 parts of fluorosilicic acid), with a water content of 11.8 parts water (with 80% SiO)₂Reaction to produce 1.6 parts water, 20% (Na)₂O, CaO) reacting to produce 0.2 part of water), and the generated fluosilicate is 0.2 part; and then uniformly recovering through a recovery barrel, and performing filter pressing through a filter press to remove the fluosilicate in the clear liquid, wherein the mass fraction of the fluosilicic acid in the clear liquid is 21.47 percent ((0.6 x 144)/((0.6 x 144) + (4 x 20) + (11.8 x 20))).

The working principle is as follows: firstly, the first step: placing 20 parts of hydrofluoric acid mixed solution into an etching tank, and placing 1 part of glass into the etching tank after being crushed by a crusher; step two: reacting gaseous silicon tetrafluoride generated by the reaction of hydrofluoric acid and glass with excessive hydrofluoric acid to generate fluosilicic acid; step three: reacting metal oxides such as sodium oxide and calcium oxide in the glass with fluosilicic acid to generate fluosilicate; step four: injecting one part of fluosilicic acid into a by-product fluosilicic acid bucket through a high-temperature acid discharge pipeline and a pump machine, and injecting the other part of fluosilicic acid into a recovery bucket through an HF recovery pipe; step five: the fluosilicic acid in the recycling barrel is connected into a filter press through an HP filter pressing pipe and a pump machine, and the fluosilicic acid salt is filtered and removed through the filter press to obtain clear liquid HF and H₂SiF₆、H₂O; step six: the clear liquid is HF, H₂SiF₆、H₂Injecting O into a recycling bin after filter pressing through a pipeline and a pump; step seven: the clear liquid is HF, H₂SiF₆、H₂After being subjected to filter pressing, the O is recycled and then is connected into an etching tank through an HF recycling pipe and a pump to react with glass to continuously consume hydrofluoric acid in the O, so that the concentration of fluosilicate is continuously increased; step eight: injecting the other part of fluosilicate into a by-product fluosilicic acid bucket through a high-temperature acid discharge pipe and a pump machine; step nine: injecting the byproduct fluosilicate in the byproduct fluosilicic acid bucket into a filter press through a pipeline and a pump machine to carry out fluorine and silicon treatmentThe concentration of acid is titrated and tested, the concentration is discharged after reaching the standard, clear liquid is pumped back to a workshop for use, the reaction rate of etching liquid and glass is reduced due to the reduction of the content of hydrofluoric acid in the recycled liquid, the heating reaction is carried out on the recycled acid liquid on the premise of meeting the production, the activity of the acid liquid is improved by heating, the intermolecular motion amount is increased so as to meet the requirement that the reaction rate of the hydrofluoric acid and the glass is constant under the condition that the content of the acid liquid is reduced, the aim of stable production is further achieved, the residual hydrofluoric acid is consumed after passing through high temperature, wherein the consumed hydrofluoric acid is 3 parts, the residual hydrofluoric acid is 1 part, the content of fluosilicic acid is 0.9 part (0.6 part is reserved before the content of the fluosilicic acid is reduced, and 0.3 part (and₂reaction to produce 0.4 portion of fluosilicic acid and 20 percent of (Na)₂O, CaO) consumes 0.1 part of fluorosilicic acid), with a water content of 12.7 parts water (11.8 parts previously left, with 0.9 parts newly formed (with 80% SiO)₂The reaction produced 0.8 part water, 20% (Na)₂O, CaO) 0.1 part of water is produced by reaction), the mass fraction of the generated fluosilicate is 32.1 percent (0.9 x 144)/((0.9 x 144) + (1 x 20) + (12.7 x 20))) after being removed by filtration, and the content of the industrial grade fluosilicic acid standard is more than or equal to 30 percent, so the generation of the by-product industrial grade fluosilicic acid can be achieved by the design, and a comparison table of the final temperature, the reaction rate and the fluosilicic acid content is calculated according to data after the process monitoring of multiple high-temperature reactions and the measurement of the content of the fluosilicic acid, so that the management of the reaction termination time of an etching site is facilitated, and the by-product of the fluosilicic acid can be visually discharged by the final temperature and the etching reaction rate.

Finally, it should be noted that the above-mentioned contents are only used for illustrating the technical solutions of the present invention, and not for limiting the protection scope of the present invention, and that the simple modifications or equivalent substitutions of the technical solutions of the present invention by those of ordinary skill in the art can be made without departing from the spirit and scope of the technical solutions of the present invention.