阅读说明：本技术 一种利用白钨渣处理含氟氯废气的方法 (Method for treating waste gas containing fluorine and chlorine by using white tungsten slag ) 是由 王瑞祥 杨裕东 钟晓聪 曾婕 刘茶香 周杰 谢辉林 王艳阳 于 2019-10-09 设计创作，主要内容包括：本发明公开了一种利用白钨渣处理含氟氯废气的方法,所述方法包括：步骤1,向装有所述白钨渣的三相反应器中,加入盐酸；步骤2,过后通入含氟氯废气,所得的除氟后液回收其中有价金属,所得的渣作为制作玻璃的原材料。本发明的优点在于“以废治废”,利用白钨渣处理含氟氯废气,成本低廉,操作简单,同时减少了白钨渣的堆存。利用该种处理方法,除氟、氯率均达到95％以上,使用所得渣制作出的玻璃性能较好,所得除氟氯后液可进一步回收钨、钽和铌等有价金属。(The invention discloses a method for treating waste gas containing fluorine and chlorine by using white tungsten slag, which comprises the following steps: step 1, adding hydrochloric acid into a three-phase reactor filled with the white tungsten slag; and 2, introducing fluorine-containing chlorine waste gas, recovering valuable metals from the obtained defluorinated liquid, and taking the obtained slag as a raw material for manufacturing glass. The method has the advantages of treating waste by waste, treating the waste gas containing fluorine and chlorine by using the white tungsten slag, having low cost and simple operation, and simultaneously reducing the stockpiling of the white tungsten slag. By utilizing the treatment method, the fluorine and chlorine removal rate is over 95 percent, the glass manufactured by using the obtained slag has better performance, and the obtained fluorine and chlorine removal liquid can further recover valuable metals such as tungsten, tantalum, niobium and the like.)

1. A method for treating waste gas containing fluorine and chlorine by using white tungsten slag is characterized by comprising the following steps:

Step 1, adding hydrochloric acid into a three-phase reactor filled with the white tungsten slag;

Step 2, introducing fluorine-containing chlorine waste gas, recovering valuable metals from the obtained defluorinated liquid, and taking the obtained slag as a raw material for manufacturing glass;

The scheelite slag is a leaching residue formed by decomposing scheelite by using a sodium hydroxide solution and a sodium carbonate solution as leaching agents.

2. The method for treating the waste gas containing the fluorine and the chlorine by using the white tungsten slag as claimed in claim 1, wherein the white tungsten slag is placed in a gas-liquid-solid three-phase reactor, hydrochloric acid is added firstly under the conditions that the temperature is 25-60 ℃ and the rotating speed is 100-400 r/min, and then the waste gas containing the fluorine and the chlorine is introduced for reaction for 1-3 hours.

3. The method for treating waste gas containing fluorine and chlorine by using white tungsten slag according to claim 1 or 2, wherein the waste gas containing fluorine and chlorine has a fluorine content of 10 to 45%, a chlorine content of 15 to 40%, and a hydrochloric acid concentration of 20 to 25%.

4. The method for treating waste gas containing fluorine and chlorine by using white tungsten slag according to any one of claims 1 to 3, wherein the gas-liquid-solid ratio of the waste gas containing fluorine and chlorine, the hydrochloric acid and the white tungsten slag is 1:1:1 to 1:6:3cm³/mL/g。

5. The method for treating a waste gas containing fluorine and chlorine using white tungsten slag according to claim 1, wherein the amount of the hydrochloric acid added is 0.8L and the concentration is 21%.

6. The method for treating waste gas containing fluorine and chlorine by using the scheelite according to claim 1, wherein the waste gas containing fluorine and chlorine is introduced for 15min after the hydrochloric acid is added.

7. The method for treating waste gas containing fluorine and chlorine by using white tungsten slag according to claim 1 or 6, wherein the amount of the waste gas containing fluorine and chlorine introduced is 1m³The fluorine content was 40% and the chlorine content was 31%.

8. A method for treating waste gas containing fluorine and chlorine by using the method as claimed in claims 1 to 4, wherein the fluorine and chlorine removal rate of the method is 95% or more.

9. A glass produced by the method for treating a waste gas containing fluorine and chlorine according to any one of claims 1 to 4, wherein the obtained glass has good properties and a high recovery rate of valuable metals extracted from a solution after fluorine removal.

Technical Field

The invention relates to the technical field of environmental protection and metallurgy, in particular to a method for treating waste gas containing fluorine and chlorine by utilizing white tungsten slag.

Background

The fluorine-containing and chlorine-containing waste gas mainly comes from fluorine chemical industry. The fluorine chemical industry generates a large amount of fluorine-containing and chlorine-containing waste gas, and various dusts are included in the waste gas. The fluorine-containing and chlorine-containing waste gas is a gas with high toxicity, strong harmfulness, and can stimulate eyes, nose, throat and respiratory tract of a human body, and when the concentration is high, the gas can cause bronchial spasm, organ ulcerative inflammation, acute pulmonary edema and the like of the human body, and can cause poisoning and death when the concentration is high. At present, no better treatment method exists.

The alkali decomposition treatment of scheelite is one of the mainstream processes for tungsten smelting in China, and the scheelite is decomposed by using a sodium hydroxide solution and a sodium carbonate solution as leaching agents to obtain leaching residue, namely scheelite slag. In the prior art, the produced white tungsten slag is piled up in the tungsten smelting production, which has great influence on the environment, and the tungsten slag is brought into dangerous waste after the environmental protection law is implemented, so the piled material and the newly produced slag are in urgent need of treatment.

Therefore, how to treat the white tungsten slag and the waste gas containing the fluorine and the chlorine simultaneously needs to be further researched.

disclosure of Invention

The invention aims to provide a method for simultaneously treating white tungsten slag and waste gas containing fluorine and chlorine, which decomposes the white tungsten slag into refractory slag and liquid after fluorine removal and can efficiently remove fluorine and chlorine in the waste gas containing fluorine and chlorine at low cost.

In order to achieve the purpose, the invention adopts the following technical scheme:

a method for treating a fluorine-chlorine-containing waste gas by using white tungsten slag, comprising the following steps:

Step 1, adding hydrochloric acid into a three-phase reactor filled with the white tungsten slag;

Step 2, introducing fluorine-containing chlorine waste gas, recovering valuable metals from the obtained defluorinated liquid, and taking the obtained slag as a raw material for manufacturing glass;

The scheelite slag is a leaching residue formed by decomposing scheelite by using a sodium hydroxide solution and a sodium carbonate solution as leaching agents.

The scheelite slag is placed in a gas-liquid-solid three-phase reactor, hydrochloric acid is added firstly under the conditions that the temperature is 25-60 ℃ and the rotating speed is 100-400 r/min, and then the fluorine-containing chlorine waste gas is introduced, and the reaction time is 1-3 hours.

the waste gas containing fluorine and chlorine is characterized in that the fluorine content is 10-45%, the chlorine content is 15-40%, and the concentration of the used hydrochloric acid is 20-25%. The gas-liquid-solid ratio of the waste gas containing the fluorine and chlorine, the hydrochloric acid and the white tungsten slag is 1:1: 1-1: 6:3cm³/mL/g。

The amount of the added hydrochloric acid was 0.8L, and the concentration was 21%.

The time for introducing the waste gas containing fluorine chloride is 15min after the hydrochloric acid is added.

the amount of the waste gas containing fluorine and chlorine was 1m³the fluorine content was 40% and the chlorine content was 31%.

The method for treating waste gas containing fluorine and chlorine by using white tungsten slag has fluorine and chlorine removing rate up to above 95%.

The glass prepared by the method for treating the waste gas containing fluorine and chlorine by utilizing the white tungsten slag has good performance, and the recovery rate of extracting valuable metals from the liquid after fluorine removal is high.

The alkali decomposition treatment of scheelite is one of the mainstream processes of tungsten smelting in China, and the scheelite is decomposed by using a sodium hydroxide solution and a sodium carbonate solution as leaching agents to obtain leaching residue, namely scheelite slag, which mainly contains calcium oxide, calcium tungstate, calcium hydroxide, magnesium hydroxide, silicon dioxide and the like. In the prior art, the produced scheelite slag is piled up in the tungsten smelting production.

the method utilizes the known components and characteristics of the white tungsten slag, combines the hydrochloric acid to treat the waste gas containing the fluorine and the chlorine, and realizes the treatment of wastes with processes of wastes against one another. Wherein, calcium oxide, calcium tungstate, calcium hydroxide and magnesium hydroxide in the white tungsten slag are decomposed under the condition of hydrochloric acid to form calcium chloride, magnesium chloride and other solution components, and after the fluorine-containing chlorine waste gas is introduced, the binding capacity of fluorine ions, calcium ions and magnesium ions is stronger than that of chlorine ions to form calcium fluoride and magnesium fluoride precipitates. The partial reaction is as follows:

Ca²⁺+2Cl^-＝CaCl₂↓

Mg²⁺+2Cl^-＝MgCl₂↓

CaCl₂+2F^-＝CaF₂+2Cl^-

MgCl₂+2F^-＝MgF₂+2Cl^-

meanwhile, the invention discovers that the scheelite slag has stronger adsorption effect on fluorine ions in the solution, and can promote the absorption and removal of fluorine in the waste gas containing fluorine and chlorine; and after chlorine in the fluorine-containing chlorine waste gas is dissolved in the solution, hydrochloric acid is formed, the consumed hydrochloric acid is supplemented, the undecomposed white tungsten slag is promoted to be decomposed and combined with chloride ions, the chlorine in the fluorine-containing chlorine waste gas is promoted to be dissolved in the solution, and finally the chloride ions are enriched in the solution. Namely, in the process of removing fluorine and chlorine, the white tungsten slag, the generated calcium chloride and the generated magnesium chloride play a synergistic role in removing fluorine and chlorine.

In the invention, because the components of the white tungsten slag are difficult to accurately determine, and the using amount of the white tungsten slag is not particularly limited, the invention finds that the fluorine and the chlorine in the waste gas containing the fluorine and the chlorine can be removed by controlling the gas-liquid-solid ratio and the reaction conditions. The fluorine and chlorine removal rate of the invention can reach more than 95%, if the effect of one-time treatment is not good, the second-time treatment can be carried out, and finally the national emission standard is reached.

In the invention, the main components of the final slag are calcium fluoride, magnesium fluoride and silicon dioxide which are used as raw materials for manufacturing glass; the obtained defluorinated liquid contains sodium tungstate and sodium chloride as main components and valuable metals are further recovered.

the invention can simultaneously realize the treatment of the white tungsten slag and the waste gas containing fluorine and chlorine, and achieve the purposes of removing fluorine and chlorine, recycling the final slag and removing fluorine after-treatment liquid. The method does not need special treatment environment, can realize rapid fluorine and chlorine removal and treat waste by waste.

drawings

FIG. 1 is a schematic flow diagram of the present invention;

Detailed Description

The present invention will be further described with reference to the accompanying drawings, and it should be noted that the following examples are provided to illustrate the detailed embodiments and specific operations based on the technical solutions of the present invention, but the scope of the present invention is not limited to the examples.

As shown in figure 1, the invention is a method for treating waste gas containing fluorine and chlorine by using white tungsten slag, which comprises the following steps:

Step 1, adding hydrochloric acid into a three-phase reactor filled with the white tungsten slag;

Step 2, introducing fluorine-containing chlorine waste gas, recovering valuable metals from the obtained defluorinated liquid, and taking the obtained slag as a raw material for manufacturing glass;

The scheelite slag is a leaching residue formed by decomposing scheelite by using a sodium hydroxide solution and a sodium carbonate solution as leaching agents.

The scheelite slag is placed in a gas-liquid-solid three-phase reactor, hydrochloric acid is added firstly under the conditions that the temperature is 25-60 ℃ and the rotating speed is 100-400 r/min, and then the fluorine-containing chlorine waste gas is introduced, and the reaction time is 1-3 hours.

the waste gas containing fluorine and chlorine is characterized in that the fluorine content is 10-45%, the chlorine content is 15-40%, and the concentration of the used hydrochloric acid is 20-25%. The gas-liquid-solid ratio of the waste gas containing the fluorine and chlorine, the hydrochloric acid and the white tungsten slag is 1:1: 1-1: 6:3cm³/mL/g。

The amount of the added hydrochloric acid was 0.8L, and the concentration was 21%.

the time for introducing the waste gas containing fluorine chloride is 15min after the hydrochloric acid is added.

the amount of the waste gas containing fluorine and chlorine was 1m³The fluorine content was 40% and the chlorine content was 31%.

The method for treating waste gas containing fluorine and chlorine by using white tungsten slag has fluorine and chlorine removing rate up to above 95%.

The glass prepared by the method for treating the waste gas containing fluorine and chlorine by utilizing the white tungsten slag has good performance, and the recovery rate of extracting valuable metals from the liquid after fluorine removal is high.