阅读说明：本技术 分解黑白钨精矿的方法与应用 (Method for decomposing wolframite concentrate and application ) 是由 钟石生 徐国钻 杨正峰 张代彬 许杰 于 2021-08-30 设计创作，主要内容包括：本发明公开了一种分解黑白钨精矿的方法与应用,该方法包括：(1)将黑白钨精矿、活化剂、水与磨球混合进行活化球磨,以便得到矿浆；(2)将矿浆进行固液分离和清洗,以便得到黑白钨细矿和废液；(3)伴随着搅拌,将黑白钨细矿与浓盐酸进行混合反应,以便得到反应后液；(4)将反应后液进行固液分离和清洗,以便得到钨酸与酸分解液。采用该方法来分解黑白钨精矿,可以有效提高黑白钨精矿的分解效率和分解效果,钨以钨酸形式达到分离,且矿中的铁、锰、钙有价元素能够得到有效回收利用。(The invention discloses a method for decomposing wolframite concentrate and application, wherein the method comprises the following steps: (1) mixing the black-white tungsten concentrate, an activating agent, water and grinding balls for activating and ball-milling to obtain ore pulp; (2) carrying out solid-liquid separation and cleaning on the ore pulp so as to obtain wolframite fine ore and waste liquid; (3) mixing and reacting the scheelite with concentrated hydrochloric acid with stirring to obtain a reacted solution; (4) and carrying out solid-liquid separation and cleaning on the reacted solution so as to obtain tungstic acid and acid decomposition solution. By adopting the method to decompose the black-and-white tungsten concentrate, the decomposition efficiency and the decomposition effect of the black-and-white tungsten concentrate can be effectively improved, tungsten is separated in the form of tungstic acid, and valuable elements such as iron, manganese and calcium in the ore can be effectively recycled.)

1. A method for decomposing wolframite concentrate is characterized by comprising the following steps:

(1) mixing the black-white tungsten concentrate, an activating agent, water and grinding balls for activating and ball-milling to obtain ore pulp;

(2) carrying out solid-liquid separation and cleaning on the ore pulp so as to obtain wolframite fine ore and waste liquid;

(3) mixing and reacting the scheelite with concentrated hydrochloric acid with stirring to obtain a reacted solution;

(4) and carrying out solid-liquid separation and cleaning on the reacted solution so as to obtain tungstic acid and acid decomposition solution.

2. The method according to claim 1, wherein in the step (1), the mass ratio of the wolframite concentrate to the activator is (1000-2000): 1.

3. the method according to claim 1, wherein in the step (1), the mass ratio of the wolframite concentrate to the grinding balls is 1: (2-5);

optionally, in the step (1), the solid-to-liquid ratio of the black-white tungsten concentrate to the water is (1-4) kg: 1L of the compound.

4. The method of claim 1, wherein in the step (1), the ball milling time is 5 to 20 hours and the rotation speed is 150 to 600 rpm.

5. The method according to claim 1, wherein in the step (3), the solid-to-liquid ratio of the scheelite to the concentrated hydrochloric acid is 1 kg: (1-4) L;

optionally, in the step (3), the rotation speed of the stirring is 200-600 r/min;

optionally, in the step (3), the reaction temperature is 60-100 ℃ and the reaction time is 1-6 hours.

6. A method of treating arsenic and/or phosphorous-containing wastewater, comprising:

(a) mixing the wastewater containing arsenic and/or phosphorus with an acid neutralizer to adjust the pH value to 5-7 so as to obtain an acid-adjusted liquid;

(b) mixing the acid-adjusted solution with the acid decomposition solution obtained by the method of any one of claims 1 to 5, adding an alkaline neutralizing agent to adjust the pH value to 6 to 9, and reacting to obtain a reacted solution;

(c) and carrying out solid-liquid separation on the reacted liquid so as to obtain filtrate and sludge.

7. The method according to claim 6, wherein in step (a), the concentration of arsenic and/or phosphorus in the wastewater containing arsenic and/or phosphorus is 2-10 mg/L.

8. The process of claim 6, wherein in step (a), the acid neutralizing agent comprises the acid decomposition solution and/or hydrochloric acid.

9. The method according to claim 7, wherein the volume ratio of the arsenic-and/or phosphorus-containing wastewater to the acid decomposition solution is (20-50): 1;

optionally, in step (b), the basic neutralizing agent comprises calcium hydroxide and/or calcium chloride.

10. The method according to claim 6, wherein in the step (b), the reaction time is 5 to 60 minutes.

Technical Field

The invention belongs to the technical field of resource recycling, and particularly relates to a method for decomposing wolframite concentrate and application thereof.

Background

At present, the mainstream method for treating the black and white tungsten concentrate (the main components are iron tungstate, manganese tungstate and calcium tungstate) by tungsten smelting is the high-temperature high-pressure decomposition of sodium hydroxide, then tungsten is separated from elements such as iron, manganese, calcium and the like through plate-and-frame filtration, so that the iron, manganese and calcium enter a slag phase in the form of ferric hydroxide, manganese hydroxide and calcium hydroxide, the slag quantity is large, the current state is qualified as dangerous waste and is difficult to treat, if the qualified unit treatment is entrusted, the treatment cost is high, and how to fully utilize valuable elements of iron, manganese and calcium in the ore, harmless treatment of tungsten slag is always a subject of attention of many tungsten smelting workers, and many domestic scholars decompose black and white tungsten concentrate by using hydrochloric acid, however, the method has the problems of long decomposition time, unstable decomposition effect, high tungsten content in slag, incapability of effectively recycling valuable metals such as iron, manganese, calcium and the like, so that the acid decomposition process cannot be efficiently utilized.

Therefore, the existing black and white tungsten concentrate decomposition technology needs to be improved.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the related art. Therefore, the invention aims to provide a method and application for decomposing black and white tungsten concentrate, the method can be used for decomposing the black and white tungsten concentrate, the decomposition efficiency and the decomposition effect of the black and white tungsten concentrate can be effectively improved, tungsten is separated in a tungstic acid form, and valuable elements such as iron, manganese and calcium in the ore can be effectively recycled.

In one aspect of the invention, a method of decomposing a wolframite concentrate is presented. According to an embodiment of the invention, the method comprises:

(1) mixing the black-white tungsten concentrate, an activating agent, water and grinding balls for activating and ball-milling to obtain ore pulp;

(2) carrying out solid-liquid separation and cleaning on the ore pulp so as to obtain wolframite fine ore and waste liquid;

(3) mixing and reacting the scheelite with concentrated hydrochloric acid with stirring to obtain a reacted solution;

(4) and carrying out solid-liquid separation and cleaning on the reacted solution so as to obtain tungstic acid and acid decomposition solution.

According to the method for decomposing the black and white tungsten concentrate, the activating agent, the water and the grinding balls are mixed for activation ball milling, the mechanical activation effect in the ball milling process is utilized, the surface substances of the black and white tungsten concentrate are continuously stripped, the separation of the black and white tungsten concentrate is enhanced, the surface energy of the newly generated substances of the tungsten concentrate can be reduced in the ball milling process, the fine particles are prevented from being re-agglomerated, the crushing efficiency is improved, and the strength of the tungsten fine ore is improved, so that tungsten, iron, manganese and calcium in the black and white tungsten concentrate are fully refined; then carrying out solid-liquid separation and cleaning on the ore pulp obtained by the activation ball milling to obtain scheelite and waste liquid; carrying out mixed reaction on the scheelite and the concentrated hydrochloric acid along with stirring, wherein tungsten in the scheelite is separated in a tungstic acid form, iron, manganese and calcium in the scheelite enter a liquid phase in a ferric chloride, manganese chloride and calcium chloride form, and compared with the prior art that the black and white tungsten concentrate is directly decomposed by hydrochloric acid without activated ball milling, the black and white tungsten concentrate is treated by adopting a mechanical activated ball milling and hydrochloric acid decomposition process, so that the black and white tungsten concentrate can be completely decomposed by acid, and the decomposition efficiency is effectively improved; and finally, carrying out solid-liquid separation and cleaning on the reacted solution to obtain the tungstic acid and acid decomposition solution. In addition, because the ferric chloride, the manganese chloride and the calcium chloride in the acid decomposition liquid completely exist in an ion form, the acid decomposition liquid can be used for treating arsenic and/or phosphorus in tungsten smelting wastewater, the effect of removing arsenic and/or phosphorus is obviously superior to that of a conventional medicament, valuable metals such as iron, manganese, calcium and the like in black and white tungsten concentrate are comprehensively utilized, the tungsten metal recovery rate is improved, and meanwhile, the treatment cost of the tungsten smelting wastewater is greatly reduced; meanwhile, the tungstic acid can be used for preparing qualified ammonium paratungstate products after ammonia dissolution and impurity removal. In conclusion, the method for decomposing the black-and-white tungsten concentrate can effectively improve the decomposition efficiency and the decomposition effect of the black-and-white tungsten concentrate, tungsten is separated in the form of tungstic acid, valuable elements such as iron, manganese and calcium in the ore can be effectively recycled, and the method has the advantages of simple equipment, less investment, simple process operation and convenience in industrialization.

In addition, the method for decomposing the scheelite concentrate according to the embodiment of the invention may also have the following additional technical features:

in some embodiments of the invention, in the step (1), the mass ratio of the wolframite concentrate to the activator is (1000-2000): 1. therefore, the decomposition efficiency and the decomposition effect of the black-white tungsten concentrate can be effectively improved.

In some embodiments of the invention, in step (1), the mass ratio of the wolframite concentrate to the grinding balls is 1: (2-5). Therefore, the decomposition efficiency and the decomposition effect of the black-white tungsten concentrate can be effectively improved.

In some embodiments of the invention, in the step (1), the solid-to-liquid ratio of the black-and-white tungsten concentrate to the water is (1-4) kg: 1L of the compound. Therefore, the decomposition efficiency and the decomposition effect of the black-white tungsten concentrate can be effectively improved.

In some embodiments of the present invention, in the step (1), the ball milling time is 5 to 20 hours, and the rotation speed is 150 to 600 rpm. Therefore, the decomposition efficiency and the decomposition effect of the black-white tungsten concentrate can be effectively improved.

In some embodiments of the invention, in step (3), the solid-to-liquid ratio of the wolframite fines to the concentrated hydrochloric acid is 1 kg: (1-4) L. Therefore, the decomposition efficiency and the decomposition effect of the black-white tungsten concentrate can be effectively improved.

In some embodiments of the invention, in the step (3), the rotation speed of the stirring is 200-600 r/min. Therefore, the decomposition efficiency and the decomposition effect of the black-white tungsten concentrate can be effectively improved.

In some embodiments of the present invention, in the step (3), the reaction temperature is 60 to 100 ℃ and the reaction time is 1 to 6 hours. Therefore, the decomposition efficiency and the decomposition effect of the black-white tungsten concentrate can be effectively improved.

In a second aspect of the invention, a method of treating arsenic and/or phosphorous-containing wastewater is provided. According to an embodiment of the invention, the method comprises:

(a) mixing the wastewater containing arsenic and/or phosphorus with an acid neutralizer to adjust the pH value to 5-7 so as to obtain an acid-adjusted liquid;

(b) mixing the acid-adjusted solution with the acid decomposition solution obtained by the method, and adding an alkaline neutralizing agent to adjust the pH value to 6-9 for reaction so as to obtain a reacted solution;

(c) and carrying out solid-liquid separation on the reacted liquid so as to obtain filtrate and sludge.

According to the method for treating the wastewater containing arsenic and/or phosphorus, the wastewater containing arsenic and/or phosphorus is mixed with an acid neutralizing agent to adjust the pH value to 5-7, then the acid-adjusted solution is mixed with the acid decomposition solution obtained by the method, an alkaline neutralizing agent is added to adjust the pH value to 6-9 for reaction, and the arsenic in the wastewater is FeAsO₄、Mn₃(AsO₄)₂、Ca₃(AsO₄)₂Precipitating phosphorus as FePO₄、Mn₃(PO₄)₂、Ca₃(PO₄)₂Precipitating in a form, and finally carrying out solid-liquid separation on the reacted liquid to obtain filtrate and sludge with arsenic/phosphorus less than 0.1 mg/L. Therefore, when the method is used for treating the arsenic and/or phosphorus-containing wastewater, the arsenic and/or phosphorus removal effect is obviously superior to that of a conventional medicament, the arsenic and/or phosphorus content in the treated reaction solution is far lower than the national environmental protection requirement (the arsenic is less than 0.5mg/L, and the phosphorus is less than 0.5mg/L), so that valuable metals such as iron, manganese, calcium and the like in the black and white tungsten concentrate are comprehensively utilized, the consumption of raw and auxiliary materials for removing the arsenic and/or phosphorus in the wastewater is reduced by 70-80%, and the treatment cost of the tungsten smelting wastewater is greatly reduced.

In addition, the method for treating arsenic-and/or phosphorus-containing wastewater according to the above embodiment of the present invention may further have the following additional technical features:

in some embodiments of the present invention, in the step (a), the concentration of arsenic and/or phosphorus in the arsenic and/or phosphorus-containing wastewater is 2 to 10 mg/L.

In some embodiments of the invention, in step (a), the acidic neutralizing agent comprises the acid decomposition liquid and/or hydrochloric acid.

In some embodiments of the invention, the volume ratio of the arsenic and/or phosphorus-containing wastewater to the acid decomposition solution is (20-50): 1. therefore, the effect of removing arsenic and/or phosphorus is better.

In some embodiments of the invention, in step (b), the basic neutralizing agent comprises calcium hydroxide and/or calcium chloride.

In some embodiments of the present invention, in the step (b), the reaction time is 5 to 60 minutes. Therefore, the effect of removing arsenic and/or phosphorus is better.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic flow diagram of a method of decomposing a wolframite concentrate according to one embodiment of the present invention;

FIG. 2 is a schematic flow diagram of a method of treating arsenic and/or phosphorus-containing wastewater according to one embodiment of the present invention;

fig. 3 is a flow chart of a process for decomposing a scheelite concentrate and respectively performing wastewater arsenic removal and ammonium paratungstate preparation on the obtained acid decomposition solution and tungstic acid according to an embodiment of the invention.

Detailed Description

The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In a first aspect of the invention, a method of decomposing a wolframite concentrate is presented. According to an embodiment of the invention, with reference to fig. 1 and 3, the method comprises:

s100: mixing the black and white tungsten concentrate, activating agent, water and grinding balls for activation ball milling

In the step, the ore pulp can be obtained by mixing the black-white tungsten concentrate, the activating agent, the water and the grinding balls for activation ball milling. The inventor finds that the mechanical activation effect in the ball milling process is utilized to continuously strip the surface substances of the black-and-white tungsten concentrate, so that the separation of the black-and-white tungsten concentrate is strengthened, the surface energy of the newly generated substances of the tungsten concentrate can be reduced, the re-agglomeration of fine particles can be prevented, the crushing efficiency is improved, the strength of the tungsten fine ore is improved, tungsten, iron, manganese and calcium in the black-and-white tungsten concentrate are fully refined, and the subsequent decomposition efficiency of concentrated hydrochloric acid on the black-and-white tungsten concentrate can be improved. Preferably, the activation ball milling process is carried out in a roller ball mill in a closed tight ball milling mode. It should be noted that the specific types of the above-mentioned activator and grinding ball are not particularly limited, and those skilled in the art can select them according to actual needs, for example, the activator is sodium dodecylbenzene sulfonate; the grinding ball is a tungsten alloy steel ball.

Further, the mass ratio of the black and white tungsten concentrate to the activating agent is (1000-2000): 1. the inventor finds that if the mass ratio of the black-white tungsten concentrate to the activating agent is too large, the activating agent is insufficient, the surface substances of the black-white tungsten concentrate are difficult to activate fully, the activity of the surface substances is low, the ball milling effect is influenced, and the decomposition rate is low; if the mass ratio of the black-white tungsten concentrate to the activating agent is too small, the activating agent is more in dosage, and the solubility of the activating agent is very low, so that the activating agent is difficult to fully dissolve, a large amount of foams are formed, and the activating effect is difficult to play. Therefore, the mass ratio of the method is favorable for the activating agent to fully exert the activating effect, and the decomposition rate of the black-white tungsten concentrate is high.

Further, the mass ratio of the black and white tungsten concentrate to the grinding balls is 1: (2-5). The inventor finds that if the mass ratio of the black-white tungsten concentrate to the grinding balls is too large, the grinding balls are small in amount, mutual collision among the grinding balls is reduced in the ball milling process, the contact amount of the black-white tungsten concentrate and the grinding balls is reduced, so that the ball milling efficiency is low, the granularity of the black-white tungsten concentrate is not fully ground, and the decomposition rate is influenced; if the mass ratio of the black-white tungsten concentrate to the grinding balls is too small, the grinding balls are large in amount, the ball milling space is reduced in the ball milling process, the collision among the grinding balls is influenced, the black-white tungsten is difficult to refine, and the decomposition rate is influenced. Therefore, the mass ratio of the method is favorable for fully grinding the black-white tungsten concentrate, and further the decomposition rate of the black-white tungsten concentrate is improved.

Further, the solid-to-liquid ratio of the wolframite concentrate to water is (1-4) kg: 1L of the compound. The inventor finds that if the solid-liquid ratio of the black-white tungsten concentrate to the water is too large, the reaction rate can be increased by higher reaction concentration, but if the reaction concentration is too high, namely the solid-liquid ratio is too large and the viscosity is high, the dispersibility of reactants in the reaction process is influenced, and the decomposition rate is low; if the solid-liquid ratio of the black-white tungsten concentrate to the water is too small, the concentration of the reactant is reduced, the reaction is not facilitated to be carried out in the forward direction, and the decomposition rate is reduced. Therefore, the solid-liquid ratio is beneficial to the activation reaction, and the decomposition rate of the black-white tungsten concentrate is further improved.

Further, the ball milling time is 5-20 hours, and the rotating speed is 150-600 rpm. The inventor finds that if the ball milling time is too long, the black-white tungsten concentrate can be fully ground, but the ball milling refinement rate is not improved, and the energy consumption is high; if the ball milling time is too short, the black-and-white tungsten concentrate cannot be fully ground, so that the decomposition rate is influenced, and meanwhile, if the rotating speed is too high, the grinding balls can do centrifugal motion and cannot be fully contacted with the black-and-white tungsten concentrate, the black-and-white tungsten concentrate cannot be fully ground, the energy consumption is high, and the decomposition rate is influenced; if the rotating speed is too low, the grinding ball will do centrifugal motion and is difficult to fully contact with the black-white tungsten concentrate, the black-white tungsten concentrate cannot be fully ground, and the decomposition rate is influenced due to large energy consumption. Therefore, the ball milling time and the rotating speed of the method are favorable for fully grinding the black-and-white tungsten concentrate, so that the decomposition rate of the black-and-white tungsten concentrate is improved, and the energy consumption is low.

S200: carrying out solid-liquid separation and cleaning on the ore pulp

In the step, the pulp is subjected to solid-liquid separation and cleaning to obtain the scheelite fine ore and the waste liquid. It should be noted that the solid-liquid separation and cleaning manners are conventional in the art, and are not described herein again.

S300: mixing and reacting the scheelite with concentrated hydrochloric acid with stirring

In this step, the scheelite fine ore and the concentrated hydrochloric acid are mixed and reacted with stirring (the stirring manner is not limited), so that a solution after the reaction can be obtained. The inventor finds that under the action of concentrated hydrochloric acid, tungsten in the scheelite fine ore is separated in the form of tungstic acid, while iron, manganese and calcium in the ore enter a liquid phase in the form of ferric chloride, manganese chloride and calcium chloride, and the reaction equation is as follows: CaWO₄+HCl＝H₂WO₄↓+CaCl₂；FeWO₄+HCl＝H₂WO₄↓+FeCl₂；MnWO₄+HCl＝H₂WO₄↓+MnCl₂Compared with the prior art that the black-and-white tungsten concentrate is directly decomposed by hydrochloric acid without activated ball milling, the method adopts the process of 'mechanically activated ball milling and hydrochloric acid decomposition' to treat the black-and-white tungsten concentrate, so that the black-and-white tungsten concentrate can be completely decomposed by acid, and the decomposition efficiency is effectively improved. Preferably, the mixing reaction process is carried out in a reaction kettle in a closed manner under the normal pressure. In addition, the obtained tungstic acid can be used for preparing a qualified ammonium paratungstate product after ammonia dissolution and impurity removal, and it needs to be noted that the specific conditions for the ammonia dissolution and impurity removal are conventional in the field, and are not described herein again.

Further, the solid-to-liquid ratio of the scheelite to the concentrated hydrochloric acid is 1 kg: (1-4) L. The inventor finds that if the solid-liquid ratio of the wolframite and the concentrated hydrochloric acid is too large, the hydrochloric acid amount is small, the viscosity is high, the hydrochloric acid and the wolframite are not completely contacted, the reaction is difficult to be carried out in the forward direction, and the decomposition rate is low; if the solid-liquid ratio of the wolframite fines to the concentrated hydrochloric acid is too small, the hydrochloric acid amount is too large, the reaction is sufficient, but the hydrochloric acid waste is large, the acid mist is large, and the operation environment is influenced. Therefore, by adopting the solid-liquid ratio of the method, on one hand, the decomposition rate of the scheelite is improved; on the other hand, the waste of hydrochloric acid and the influence of larger acid mist on the operating environment can be avoided.

Further, the rotating speed of the stirring is 200-600 r/min. The inventor finds that if the stirring rotating speed is too high, the equipment shakes greatly, so that the equipment is easy to cause sealing abrasion; if the stirring speed is too low, the scheelite fine ore is difficult to stir up, cannot be in full contact with the acid, and is difficult to fully react with the acid, thereby affecting the decomposition rate. Therefore, the rotating speed of the method is favorable for improving the decomposition rate of the scheelite on the one hand; on the other hand, the equipment sealing abrasion can be avoided.

Further, the reaction temperature is 60-100 ℃ and the reaction time is 1-6 hours. The inventor finds that if the reaction temperature is too high, the influence on the decomposition rate is not great, and the energy consumption is great; if the reaction temperature is too low, the reaction heat energy is small, the normal reaction is not facilitated, and the reaction decomposition rate is reduced. Meanwhile, if the time is too long, the reaction decomposition rate is not greatly influenced and the energy consumption is large if the time is too long; if the time is too short, the reaction is insufficient, and the reaction decomposition rate is affected. Therefore, the reaction temperature and time are favorable for improving the decomposition rate of the scheelite and the scheelite fine ore, and the energy consumption is low.

The inventor finds that by mixing the black-and-white tungsten concentrate, the activating agent and water with the grinding balls for activation ball milling, the mechanical activation effect in the ball milling process is utilized to continuously strip the surface substances of the black-and-white tungsten concentrate, the separation of the black-and-white tungsten concentrate is enhanced, the surface energy of the newly generated substances of the tungsten concentrate can be reduced and the re-agglomeration of fine particles can be prevented in the ball milling process, the crushing efficiency is improved, and the strength of the tungsten fine ore is improved, so that tungsten, iron, manganese and calcium in the black-and-white tungsten concentrate are fully refined; then carrying out solid-liquid separation and cleaning on the ore pulp obtained by the activation ball milling to obtain scheelite and waste liquid; carrying out mixed reaction on the scheelite and the concentrated hydrochloric acid along with stirring, wherein tungsten in the scheelite is separated in a tungstic acid form, iron, manganese and calcium in the scheelite enter a liquid phase in a ferric chloride, manganese chloride and calcium chloride form, and compared with the prior art that the black and white tungsten concentrate is directly decomposed by hydrochloric acid without activated ball milling, the black and white tungsten concentrate is treated by adopting a mechanical activated ball milling and hydrochloric acid decomposition process, so that the black and white tungsten concentrate can be completely decomposed by acid, and the decomposition efficiency is effectively improved; and finally, carrying out solid-liquid separation and cleaning on the reacted solution to obtain the tungstic acid and acid decomposition solution. In addition, because the ferric chloride, the manganese chloride and the calcium chloride in the acid decomposition liquid completely exist in an ion form, the acid decomposition liquid can be used for treating arsenic and/or phosphorus in tungsten smelting wastewater, the effect of removing arsenic and/or phosphorus is obviously superior to that of a conventional medicament, valuable metals such as iron, manganese, calcium and the like in black and white tungsten concentrate are comprehensively utilized, the tungsten metal recovery rate is improved, and meanwhile, the treatment cost of the tungsten smelting wastewater is greatly reduced; meanwhile, the tungstic acid can be used for preparing qualified ammonium paratungstate products after ammonia dissolution and impurity removal. In conclusion, the method for decomposing the black-and-white tungsten concentrate can effectively improve the decomposition efficiency and the decomposition effect of the black-and-white tungsten concentrate, tungsten is separated in the form of tungstic acid, valuable elements such as iron, manganese and calcium in the ore can be effectively recycled, and the method has the advantages of simple equipment, less investment, simple process operation and convenience in industrialization.

In a second aspect of the invention, a method of treating arsenic and/or phosphorous-containing wastewater is provided. According to an embodiment of the invention, with reference to fig. 2 and 3, the method comprises:

sa: mixing the arsenic and/or phosphorus-containing wastewater with an acid neutralizing agent to adjust the pH value to 5-7

In the step, the pH value of the wastewater containing arsenic and/or phosphorus and an acid neutralizer is mixed to be adjusted to 5-7, and the effect of removing arsenic and/or phosphorus is optimal within the pH range, so that the acid-adjusted liquid is obtained. Specifically, the wastewater is tungsten smelting wastewater, and the concentration of arsenic and/or phosphorus in the wastewater is 2-10 mg/L. The specific type of the acid neutralizing agent can be selected by those skilled in the art according to the actual needs, and for example, the acid neutralizing agent is the acid decomposition solution and/or hydrochloric acid, preferably the acid decomposition solution. The inventor finds that the acid decomposition liquid is used as the acid neutralizing agent, so that the acid decomposition liquid can be further comprehensively recycled, and the treatment cost of the tungsten smelting wastewater is reduced. In addition, since a small amount of precipitate is generated in the above-mentioned acid adjustment process, it is preferable to obtain a solution after the acid adjustment by filtering after the acid adjustment.

Sb: mixing the acid-adjusted solution with the acid decomposition solution, adding an alkaline neutralizing agent to adjust the pH value to 6-9, and reacting

In the step, the acid-adjusted liquid is mixed with the acid decomposition liquid, an alkaline neutralizing agent is added to adjust the pH value to 6-9 for reaction, and the arsenic in the wastewater is FeAsO₄、Mn₃(AsO₄)₂、Ca₃(AsO₄)₂Precipitating phosphorus as FePO₄、Mn₃(PO₄)₂、Ca₃(PO₄)₂To obtain a reaction solution. The inventor finds that because the acid decomposition liquid is acidic, the pH value of the acid-regulated liquid is reduced after the acid decomposition liquid is added, so that the pH value needs to be regulated to 6-9 by adding an alkaline neutralizing agent to ensure better phosphorus and/or arsenic removal effect. The reaction equation for the above process is as follows: AsO₄ ^3-+Fe³⁺＝FeAsO₄↓；2AsO₄ ^3-+3Mn²⁺＝Mn₃(AsO₄)₂↓；2AsO₄ ^3-+Ca²⁺＝Ca³(AsO⁴)²↓；PO₄ ^3-+Fe³⁺＝FePO₄↓；2PO₄ ^3-+3Mn²⁺＝Mn₃(PO₄)₂↓；2PO₄ ^3-+Ca²⁺＝Ca³(PO⁴)²↓. It should be noted that the specific type of the above-mentioned alkaline neutralizing agent is not particularly limited, and may be selected by those skilled in the art according to actual needs, for example, the alkaline neutralizing agent includes calcium hydroxide and/or calcium chloride, preferably calcium hydroxide. The inventors have found that the addition of calcium chloride only fine-tunes the pH to around 6, whereas the addition of calcium hydroxide adjusts the pH over a wider range.

Further, in the step, the volume ratio of the arsenic and/or phosphorus-containing wastewater to the acid decomposition liquid is (20-50): 1. the inventor finds that if the volume ratio is too large, the pH value of the wastewater cannot be adjusted to 6-9, and the removal effect of arsenic and/or phosphorus in the wastewater is poor; if the volume ratio is too small, the pH of the wastewater is too low and becomes acidic, so that a large amount of alkaline neutralizing agent needs to be added, the cost is increased, and the acid decomposition solution is wasted. Therefore, by adopting the volume ratio of the method, on one hand, the best removal effect of arsenic and/or phosphorus in the wastewater can be achieved; on the other hand, the cost increase and the waste of the acid decomposition liquid can be avoided.

Further, the reaction time is 5 to 60 minutes. The inventors have found that if the reaction time is too long, the removal efficiency of arsenic and/or phosphorus is low; if the reaction time is too short, the removal effect of arsenic and/or phosphorus in the wastewater is not good.

And (C) Sc: carrying out solid-liquid separation on the liquid after reaction

In the step, the liquid after the reaction is subjected to solid-liquid separation to obtain filtrate and sludge, so that arsenic and/or phosphorus in the wastewater are effectively removed. The specific form of the solid-liquid separation is not particularly limited, and those skilled in the art can select the solid-liquid separation according to actual needs, for example, the solid-liquid separation can be performed by filtration.

The inventors have found that by first containing arsenic and/or phosphorusMixing the wastewater with an acidic neutralizing agent to adjust the pH value to 5-7, then mixing the acid-adjusted solution with the acid decomposition solution obtained by the method, adding an alkaline neutralizing agent to adjust the pH value to 6-9 for reaction, and reacting arsenic in the wastewater with FeAsO₄、Mn₃(AsO₄)₂、Ca₃(AsO₄)₂Precipitating phosphorus as FePO₄、Mn₃(PO₄)₂、Ca₃(PO₄)₂Precipitating in a form, and finally carrying out solid-liquid separation on the reacted liquid to obtain filtrate and sludge with arsenic/phosphorus less than 0.1 mg/L. Therefore, when the method is used for treating the arsenic and/or phosphorus-containing wastewater, the arsenic and/or phosphorus removal effect is obviously superior to that of a conventional medicament, and the arsenic and/or phosphorus content in the treated reaction solution is far lower than the national environmental protection requirement (the arsenic is less than 0.5mg/L and the phosphorus is less than 0.5mg/L), so that valuable metals such as iron, manganese, calcium and the like in the black and white tungsten concentrate are comprehensively utilized, the consumption of raw and auxiliary materials for removing the arsenic and/or phosphorus in the wastewater is reduced by 70-80%, and the treatment cost of the tungsten smelting wastewater is greatly reduced.

The following embodiments of the present invention are described in detail, and it should be noted that the following embodiments are exemplary only, and are not to be construed as limiting the present invention. In addition, all reagents used in the following examples are commercially available or can be synthesized according to methods herein or known, and are readily available to those skilled in the art for reaction conditions not listed, if not explicitly stated.

Example 1

Activating and ball milling:

1000kg of black and white tungsten concentrate is taken, and the main components of the black and white tungsten concentrate are as follows:

adding the black and white tungsten concentrate into roller ball mills in two batches, adding 1000kg of tungsten alloy steel balls into each ball mill, adding 250L of water and 0.5kg of activating agent sodium dodecyl benzene sulfonate, tightly and tightly milling at the rotating speed of 600rpm for 18 hours in a closed manner, discharging and cleaning the tungsten alloy steel balls, and filtering to obtain the scheelite fine ore and the waste liquid.

Decomposing with hydrochloric acid:

to 6m³Adding 3m into the decomposition stirring tank³Adding 1000kg of activated ball-milled wolframite fine ore into a reaction tank according to the solid-to-solid ratio of 3L:1kg of concentrated hydrochloric acid to wolframite fine ore liquid, reacting at 90 ℃, stirring for 3 hours, filtering and washing to obtain tungstic acid and acid decomposition liquid, supplying the filtrate into a decomposition filtrate tank, and controlling the total amount of the filtrate and slag washing water in the filtrate tank to be 5m³Drying 150g of tungstic acid prepared by decomposition, and detecting that the tungstic acid contains WO₃85.8 wt%, adding 100g of tungstic acid into 280mL of 5.5N concentrated ammonia water for ammonia dissolution, sealing the ammonia solution at normal pressure, controlling the temperature at 25 ℃ and the ammonia dissolution time at 2.5 hours, filtering and detecting, and measuring the content of ammonia dissolution residues to be 34.2g, wherein the residues contain WO₃33.97 wt.%, ammonia solution WO₃275g/L concentration and 270mL ammonia solution volume, the ammonia dissolution rate of the decomposed tungstic acid is 86.6 percent by calculation, 50g of tungstic acid is added into 100mL of 10 wt% liquid alkali for alkali dissolution, the alkali dissolution is normal temperature and pressure, the alkali dissolution time is 1 hour, the solution is filtered and weighed, 3.5g of alkali dissolution slag is measured, and the slag contains WO₃2.5 wt%, and the decomposition rate of ball milling with sodium dodecylbenzene sulfonate added as an active agent is calculated to be 99.79%.

Removing arsenic from acid decomposition liquid wastewater:

taking 100m at normal temperature³Tungsten smelting wastewater with arsenic concentration of 7.52mg/L is treated by adjusting pH of the wastewater to 6.5 with the acid decomposition solution, and then 2m³And (3) stirring the acid decomposition solution for 15 minutes, supplementing calcium hydroxide to adjust the pH value to 8.5, stirring for 15 minutes, and filtering to obtain a filtrate and arsenic-removing sludge, wherein the concentration of arsenic in the filtrate is 0.21mg/L, and the removal rate of arsenic in the wastewater reaches 97.2%.

Example 2

Activating and ball milling:

1000kg of black and white tungsten concentrate is taken, and the main components of the black and white tungsten concentrate are as follows:

adding the black and white tungsten concentrate into roller ball mills in two batches, adding 1000kg of tungsten alloy steel balls into each ball mill, adding 250L of water and 0.5kg of activating agent sodium dodecyl benzene sulfonate, tightly and tightly milling at the rotating speed of 600rpm for 18 hours in a closed manner, discharging and cleaning the tungsten alloy steel balls, and filtering to obtain the scheelite fine ore and the waste liquid.

Decomposing with hydrochloric acid:

to 6m³Adding 3m into the decomposition stirring tank³Adding 1000kg of activated ball-milled wolframite fine ore into a reaction tank according to the solid-to-solid ratio of 3L:1kg of concentrated hydrochloric acid to wolframite fine ore liquid, reacting at 90 ℃, stirring for 3 hours, filtering and washing to obtain tungstic acid and acid decomposition liquid, supplying the filtrate into a decomposition filtrate tank, and controlling the total amount of the filtrate and slag washing water in the filtrate tank to be 5m³Drying 150g of tungstic acid prepared by decomposition, and detecting that the tungstic acid contains WO₃87.9 wt%, adding 100g of tungstic acid into 280mL of 5.5N concentrated ammonia water for ammonia dissolution, sealing the ammonia solution at normal pressure, controlling the temperature at 25 ℃ and the ammonia dissolution time at 2.5 hours, filtering and detecting, and measuring that the ammonia dissolution residue is 36.8g and the residue contains WO₃37.06% by weight of ammonia solution WO₃The concentration is 273g/L, the volume of ammonia solution is 272mL, the dissolution rate of decomposed tungstic acid ammonia is 84.4 percent by calculation, 50g of tungstic acid is added into 100mL of liquid alkali with the concentration of 10wt percent for alkali dissolution, the alkali dissolution is normal temperature and pressure, the alkali dissolution time is 1 hour, the solution is filtered and weighed, the measured alkali dissolution residue is 4.3g, the residue contains WO₃The content of the active agent is 2.75 wt%, and the calculated decomposition rate of ball milling by adding the sodium dodecyl benzene sulfonate serving as the active agent is 99.73%.

Removing arsenic from acid decomposition liquid wastewater:

taking 100m at normal temperature³Tungsten smelting wastewater with arsenic concentration of 8.43mg/L is treated by adjusting pH to 7 with the acid decomposition solution, and then 2m³And (3) stirring the acid decomposition solution for 15 minutes, supplementing calcium hydroxide to adjust the pH value to 8.2, stirring for 15 minutes, and filtering to obtain a filtrate and arsenic-removing sludge, wherein the concentration of arsenic in the filtrate is 0.18mg/L, and the removal rate of arsenic in the wastewater reaches 97.8%.

Example 3

Adding the black and white tungsten concentrate obtained in the example 1 into roller ball mills in two batches, adding 1000kg of tungsten alloy steel balls into each ball mill, adding 250L of water and 0.5kg of activating agent sodium dodecyl benzene sulfonate, performing closed fastening ball milling at the rotating speed of 600rpm for 8 hours, discharging and cleaning the tungsten alloy steel balls, and filtering to obtain the fine scheelite and the waste liquid.

Decomposing with hydrochloric acid:

to 6m³Adding 2m into the decomposition stirring tank³Adding 1000kg of activated ball-milled wolframite fine ore into a reaction tank according to the solid-to-solid ratio of 2L:1kg of concentrated hydrochloric acid to wolframite fine ore liquid, reacting at 70 ℃, stirring for 5 hours, filtering and washing to obtain tungstic acid and acid decomposition liquid, supplying the filtrate into a decomposition filtrate tank, and controlling the total amount of the filtrate and slag washing water in the filtrate tank to be 5m³Drying 150g of tungstic acid prepared by decomposition, and detecting that the tungstic acid contains WO₃89.2 wt%, adding 100g of tungstic acid into 280mL of 5.5N concentrated ammonia water for ammonia dissolution, sealing the ammonia solution at normal pressure, controlling the temperature at 25 ℃ and the ammonia dissolution time at 2.5 hours, and filtering and detecting to obtain 40.8/g of ammonia dissolution slag containing WO₃39.06 wt.%, ammonia solution WO₃The concentration is 253g/L, the volume of ammonia solution is 278mL, the dissolution rate of decomposed tungstic acid ammonia is 82.13 percent through calculation, 50g of tungstic acid is added into 100mL of liquid alkali with the concentration of 10wt percent for alkali dissolution, the alkali dissolution is normal temperature and pressure, the alkali dissolution time is 1 hour, the solution is filtered and weighed, the measured alkali dissolution slag is 6.3g, the slag contains WO₃The content of the active agent is 4.25 wt%, and the calculated decomposition rate of ball milling by adding the sodium dodecyl benzene sulfonate serving as the active agent is 99.39%.

Removing phosphorus from acid decomposition liquid wastewater:

taking 100m at normal temperature³Tungsten smelting wastewater with phosphorus concentration of 2.47mg/L is treated with the acid decomposition solution to adjust the pH value of the wastewater to 6.5, and then 3m of the acid decomposition solution is added³And (3) stirring the acid decomposition solution for 15 minutes, supplementing calcium hydroxide to adjust the pH value to 8.5, stirring for 15 minutes, and filtering to obtain a filtrate and arsenic-removing sludge, wherein the phosphorus concentration in the filtrate is 0.1mg/L, and the removal rate of phosphorus in the wastewater reaches 99.39%.

Example 4

Adding the black and white tungsten concentrate obtained in the example 2 into roller ball mills in two batches, adding 1000kg of tungsten alloy steel balls into each ball mill, adding 250L of water and 0.5kg of activating agent sodium dodecyl benzene sulfonate, performing closed fastening ball milling at the rotating speed of 600rpm for 12 hours, discharging and cleaning the tungsten alloy steel balls, and filtering to obtain the fine scheelite and the waste liquid.

Decomposing with hydrochloric acid:

to 6m³Adding 4m into the decomposition stirring tank³Adding 1000kg of activated ball-milled wolframite fine ore into a reaction tank according to the solid-to-solid ratio of 4L:1kg of the hydrochloric acid to the wolframite fine ore liquid, reacting at 80 ℃, stirring for 4 hours, filtering and washing to obtain tungstic acid and acid decomposition liquid, supplying the filtrate into a decomposition filtrate tank, and controlling the total amount of the filtered filtrate and slag washing water in the filtrate tank to be 5m³Drying 150g of tungstic acid prepared by decomposition, and detecting that the tungstic acid contains WO₃86.5 wt%, adding 100g of tungstic acid into 280mL of 5.5N concentrated ammonia water for ammonia dissolution, sealing the ammonia solution at normal pressure, controlling the temperature at 25 ℃ and the ammonia dissolution time at 2.5 hours, filtering and detecting, and measuring the content of ammonia dissolution residues to be 33.8g, wherein the residues contain WO₃32.78 wt.%, ammonia solution WO₃The concentration is 272g/L, the volume of ammonia solution is 274mL, the dissolution rate of decomposed tungstic acid ammonia is 87.19 percent by calculation, 50g of tungstic acid is added into 100mL of liquid alkali with the concentration of 10wt percent for alkali dissolution, the alkali dissolution is normal temperature and pressure, the alkali dissolution time is 1 hour, the solution is filtered and weighed, the measured alkali dissolution residue is 3.4g, the residue contains WO₃2.3 wt%, and the decomposition rate of ball milling with sodium dodecylbenzene sulfonate added as an active agent is calculated to be 99.81%.

Removing arsenic and phosphorus from acid decomposition liquid wastewater:

taking 100m at normal temperature³Tungsten smelting wastewater with arsenic concentration of 7.52mg/L and phosphorus concentration of 2.47mg/L is treated with the acid decomposition solution to adjust the pH value of the wastewater to 6.5, and then 4m³And (3) stirring the acid decomposition solution for 15 minutes, supplementing calcium hydroxide to adjust the pH value to 8.5, stirring for 15 minutes, and filtering to obtain a filtrate and arsenic-removing sludge, wherein the concentration of arsenic in the filtrate is 0.12mg/L, the concentration of phosphorus in the filtrate is 0.1mg/L, the removal rate of arsenic in the wastewater reaches 98.4%, and the removal rate of phosphorus reaches 99.59%.

Comparative example 1

Adding the black and white tungsten concentrate obtained in the example 1 into roller ball mills in two batches, adding 1000kg of tungsten alloy steel balls into each ball mill, adding 250L of water, adding no sodium dodecyl benzene sulfonate as an activating agent, performing closed and tight ball milling at the rotating speed of 600rpm for 18 hours, discharging and cleaning the tungsten alloy steel balls, and filtering to obtain the fine tungsten black and white ore and waste liquid.

Decomposing with hydrochloric acid:

to 6m³Adding 3m into the decomposition stirring tank³Adding 1000kg of activated ball-milled wolframite fine ore into a reaction tank according to the solid-to-solid ratio of 3L:1kg of concentrated hydrochloric acid to wolframite fine ore liquid, reacting at 90 ℃, stirring for 3 hours, filtering and washing to obtain tungstic acid and acid decomposition liquid, supplying the filtrate into a decomposition filtrate tank, and controlling the total amount of the filtrate and slag washing water in the filtrate tank to be 5m³Drying 150g of tungstic acid prepared by decomposition, and detecting that the tungstic acid contains WO₃88.9 wt%, adding 100g tungstic acid into 280mL of 5.5N concentrated ammonia water, dissolving ammonia under normal pressure at 25 deg.C for 2.5 hr, filtering, and detecting to obtain 55.8g residue containing WO₃38.8 wt.%, ammonia solution WO₃The concentration is 175g/L, the volume of ammonia solution is 270mL, the dissolution rate of decomposed tungstic acid ammonia is 71.51 percent by calculation, 50g of tungstic acid is added into 100mL of liquid alkali with the concentration of 10wt percent for alkali dissolution, the alkali dissolution is normal temperature and pressure, the alkali dissolution time is 1 hour, the solution is filtered and weighed, 9.5g of alkali dissolution slag is measured, and the slag contains WO₃26.75 wt%, and the decomposition rate of the ball mill with sodium dodecylbenzene sulfonate added as an active agent is 94.28%.

Removing arsenic from acid decomposition liquid wastewater:

taking 100m at normal temperature³Tungsten smelting wastewater with arsenic concentration of 7.97mg/L is treated by adjusting pH of the wastewater to 6.5 with the acid decomposition solution, and then 2m³And (3) stirring the acid decomposition solution for 15 minutes, supplementing calcium hydroxide to adjust the pH value to 8.5, stirring for 15 minutes, and filtering to obtain filtrate and arsenic-removing sludge, wherein the concentration of arsenic in the filtrate is 0.65mg/L, and the removal rate of arsenic in the wastewater reaches 91.84%.

Comparative example 2

Adding the black and white tungsten concentrate obtained in the example 2 into roller ball mills in two batches, adding 1000kg of tungsten alloy steel balls into each ball mill, adding 250L of water, adding no sodium dodecyl benzene sulfonate as an activating agent, performing closed and tight ball milling at the rotating speed of 600rpm for 18 hours, discharging and cleaning the tungsten alloy steel balls, and filtering to obtain the fine tungsten black and white ore and waste liquid.

Decomposing with hydrochloric acid:

to 6m³Adding 3m into the decomposition stirring tank³Adding 1000kg of activated ball-milled wolframite fine ore into a reaction tank according to the solid-to-solid ratio of 3L:1kg of concentrated hydrochloric acid to wolframite fine ore liquid, reacting at 90 ℃, stirring for 3 hours, filtering and washing to obtain tungstic acid and acid decomposition liquid, supplying the filtrate into a decomposition filtrate tank, and controlling the total amount of the filtrate and slag washing water in the filtrate tank to be 5m³Drying 150g of tungstic acid prepared by decomposition, and detecting that the tungstic acid contains WO₃86.32 wt%, adding 100g tungstic acid into 280mL of 5.5N concentrated ammonia water for ammonia dissolution, sealing the ammonia dissolution under normal pressure, controlling the temperature at 25 ℃ and the ammonia dissolution time at 2.5 hours, filtering and detecting to obtain 45.8g ammonia dissolution slag containing WO₃42.87 wt.%, ammonia solution WO₃The concentration is 198g/L, the volume of ammonia solution is 270mL, the dissolution rate of decomposed tungstic acid ammonia is 77.25% by calculation, 50g of tungstic acid is added into 100mL of liquid alkali with the concentration of 10 wt% for alkali dissolution, the alkali dissolution is normal temperature and pressure, the alkali dissolution time is 1 hour, the solution is filtered and weighed, 7.34g of alkali dissolution slag is measured, and the slag contains WO₃The content of the active agent in the ball mill is 28.14 wt%, and the decomposition rate of the ball mill with the added sodium dodecyl benzene sulfonate as the active agent is calculated to be 95.22%.

Removing arsenic from acid decomposition liquid wastewater:

taking 100m at normal temperature³Tungsten smelting wastewater with arsenic concentration of 8.52mg/L is treated by adjusting pH of the wastewater to 6.5 with the acid decomposition solution, and then 2m³And (3) stirring the acid decomposition solution for 15 minutes, supplementing calcium hydroxide to adjust the pH value to 8.5, stirring for 15 minutes, filtering to obtain filtrate and arsenic-removing sludge, wherein the concentration of arsenic in the filtrate is 0.58mg/L, removing fluorine and adjusting the pH value to achieve standard discharge, and the removal rate of arsenic in the wastewater reaches 93.2%.

Comparative example 3

Taking 100m at normal temperature³Tungsten smelting wastewater with arsenic concentration of 7.86mg/L and common hydrochloric acid for adjusting the pH valueAdjusting to 6.5, adding 2m³Stirring ferrous sulfate medicament (the concentration of the medicament is prepared to be 160g/L) for 15 minutes, supplementing calcium hydroxide to adjust the pH value to 8.5, stirring for 15 minutes, filtering to obtain filtrate and arsenic-removing sludge, wherein the concentration of arsenic in the filtrate is 0.35mg/L, removing fluorine and adjusting the pH value to achieve the standard and discharging, and the removal rate of arsenic in the wastewater reaches 95.54%.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.