阅读说明：本技术 钨冶炼协同除硅的方法 (Method for removing silicon by tungsten smelting ) 是由 杨正 许圳安 王海军 于 2021-01-18 设计创作，主要内容包括：本发明公开了一种钨冶炼协同除硅的方法,包括以下步骤：S1、将钨矿与除硅剂、磷酸钠和水混合,得到第一浆料；S2、在预设温度和预设压力条件下,对第一浆料进行处理,得到处理后的料液；S3、向料液中加入除磷剂,得到第二浆料；S4、将第二浆料进行过滤,得到钨渣和钨酸钠浓料；其中,除硅剂包括铝酸钠和氧化镁。根据本发明的钨冶炼协同除硅的方法,通过使用铝酸钠和氧化镁作为除硅剂进行协同除硅,不会和其他杂质反应而引入新的杂质,铝酸钠还可起到絮凝剂的作用,使生成的不溶物质沉淀颗粒变大,易于从浆料中析出,达到更好的除硅效果,提高了产品钨的品质,而且氧化镁价格低廉,可有效地节约钨除硅成本,大大降低了钨的生产成本。(The invention discloses a method for removing silicon by tungsten smelting, which comprises the following steps: s1, mixing the tungsten ore with a silicon removing agent, sodium phosphate and water to obtain first slurry; s2, processing the first slurry under the conditions of preset temperature and preset pressure to obtain processed feed liquid; s3, adding a phosphorus removing agent into the feed liquid to obtain a second slurry; s4, filtering the second slurry to obtain tungsten slag and a sodium tungstate concentrated material; wherein the silicon removing agent comprises sodium aluminate and magnesium oxide. According to the method for removing silicon by tungsten smelting, sodium aluminate and magnesium oxide are used as the silicon removing agent to remove silicon synergistically, new impurities cannot be introduced due to reaction with other impurities, the sodium aluminate can also play a role of a flocculating agent, so that generated insoluble substances are enlarged in precipitate particles and are easy to separate out from slurry, a better silicon removing effect is achieved, the quality of tungsten is improved, the magnesium oxide is low in price, the cost of removing silicon by tungsten can be effectively saved, and the production cost of tungsten is greatly reduced.)

1. The method for removing silicon by tungsten smelting is characterized by comprising the following steps:

s1, mixing the tungsten ore with a silicon removing agent, sodium phosphate and water to obtain first slurry;

s2, processing the first slurry under the conditions of preset temperature and preset pressure to obtain processed feed liquid;

s3, adding a phosphorus removing agent into the feed liquid to obtain a second slurry;

s4, filtering the second slurry to obtain tungsten slag and a sodium tungstate concentrated material;

wherein the silicon removing agent comprises sodium aluminate and magnesium oxide.

2. The method for the synergistic silicon removal through the tungsten smelting according to claim 1, wherein the mass ratio of the usage amount of the tungsten ore to the total usage amount of the silicon removing agent, the sodium phosphate and the water is 1 (0.3-3).

3. The method for the synergistic silicon removal in the tungsten smelting process according to claim 1, wherein the mass ratio of the sodium aluminate to the magnesium oxide in the silicon removal agent is 1 (0.5-2).

4. The method for synergic silicon removal by tungsten smelting according to claim 3, characterized in that the concentration of aluminum ions in the solution of sodium aluminate is 30g/l to 40 g/l.

5. The method for tungsten smelting and silicon removal as claimed in claim 1, wherein the step S1 comprises:

s11, adding a first volume of water into the reaction tank and starting stirring;

and S12, sequentially adding the silicon removing agent, the sodium phosphate and the tungsten ore into the reaction tank under a stirring state to obtain the first slurry.

6. The method for the synergistic silicon removal through the tungsten smelting according to the claim 1, wherein in the step S2, the preset temperature is 150 ℃ to 170 ℃.

7. The method for synergic silicon removal by tungsten smelting according to claim 6, characterized in that the preset pressure is 0.8MPa to 1.0 MPa.

8. The method for tungsten smelting and silicon removal as claimed in claim 7, wherein the time for treating the first slurry is 1.5-2 hours.

9. The method for removing silicon through tungsten smelting synergism of claim 1, wherein the phosphorus removing agent is calcium carbonate, and the mass ratio of phosphorus to calcium carbonate in the feed liquid is 1 (3-5).

10. The method for tungsten smelting synergistic silicon removal according to claim 1, further comprising:

and S5, carrying out ion exchange treatment on the sodium tungstate concentrated material.

Technical Field

The invention relates to the technical field of tungsten metallurgy, in particular to a method for removing silicon by tungsten smelting in a synergistic manner.

Background

Silicon is an element which is very common, however, it rarely occurs in nature in the form of a simple substance, but is widely present in rocks, gravels, dust in the form of complex silicates or silica. With the continuous development and utilization of tungsten resources, the tungsten ore has a decreasing taste and more complex components. The difficulty of ore dressing and metallurgy is increased from the aspect of processing of raw materials, and along with the rapid development of scientific technology, users put higher requirements on product purity. The sodium tungstate solution produced by the pyrogenic process treatment of tungsten concentrate followed by alkaline decomposition usually contains impurities such as silicon, phosphorus, arsenic, molybdenum, sulfur and the like. The sodium tungstate solution containing impurities can ensure the quality of the product only by impurity removal treatment.

The high silicon content in tungsten ore causes inconvenience to the tungsten ore smelting process. Firstly, the tungsten ore has high silicon dioxide content, which causes low tungsten ore taste; secondly, the content of silicon dioxide in the tungsten ore is high, so that the decomposition process of the phosphate of the tungsten ore can be restricted, the dephosphorization effect of the sodium tungstate solution is reduced, a large amount of silica gel is generated in the ion exchange treatment process, cations such as K and the like are adsorbed, the adsorption capacity is reduced, and the product quality is influenced; thirdly, the content of silicon dioxide in tungsten ore is high, and the silicon content in waste water generated in the production process is increased, which can cause the cost for treating the waste water to be increased.

However, the existing method only uses sodium aluminate to remove silicon, and the method has the defects that the price of sodium aluminate is high, the cost of silicon removal is high, and the production cost of tungsten is overhigh.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a method for removing silicon by tungsten smelting in a synergistic manner, which can solve the problem of high cost of removing silicon by tungsten smelting in the prior art.

The method for removing silicon by tungsten smelting comprises the following steps: s1, mixing the tungsten ore with a silicon removing agent, sodium phosphate and water to obtain first slurry; s2, processing the first slurry under the conditions of preset temperature and preset pressure to obtain processed feed liquid; s3, adding a phosphorus removing agent into the feed liquid to obtain a second slurry; s4, filtering the second slurry to obtain tungsten slag and a sodium tungstate concentrated material; wherein the silicon removing agent comprises sodium aluminate and magnesium oxide.

According to the method for removing silicon by tungsten smelting in a synergic manner, sodium aluminate and magnesium oxide are used as silicon removing agents to remove silicon in a synergic manner, the sodium aluminate and the magnesium oxide do not react with other impurities to introduce new impurities, the sodium aluminate can also play a role of a flocculating agent to enable generated silicic acid, magnesium silicate and the like to gather together, so that generated insoluble substances are large in precipitate particles, are easy to separate out of slurry and filter out in a subsequent flow in a pressing manner, a better silicon removing effect can be achieved, the quality of tungsten is improved, the magnesium oxide is low in price, the cost for removing silicon by tungsten can be effectively saved, and the production cost of tungsten is greatly reduced.

The method for tungsten smelting synergistic silicon removal according to the embodiment of the invention can also have the following additional technical characteristics:

according to one embodiment of the invention, the mass ratio of the tungsten ore to the total amount of the silicon removing agent, the sodium phosphate and the water is 1 (0.3-3).

According to one embodiment of the invention, in the silicon removing agent, the mass ratio of the sodium aluminate to the magnesium oxide is 1 (0.5-2).

According to one embodiment of the invention, the concentration of aluminum ions in the sodium aluminate solution is between 30g/l and 40 g/l.

According to an embodiment of the present invention, the step S1 includes: s11, adding a first volume of water into the reaction tank and starting stirring; and S12, sequentially adding the silicon removing agent, the sodium phosphate and the tungsten ore into the reaction tank under a stirring state to obtain the first slurry.

According to an embodiment of the present invention, in the step S2, the preset temperature is 150 ℃ to 170 ℃.

According to an embodiment of the invention, the predetermined pressure is between 0.8MPa and 1.0 MPa.

According to one embodiment of the invention, the first slurry treatment time is 1.5h to 2 h.

According to one embodiment of the invention, the phosphorus removal agent is calcium carbonate, and the mass ratio of phosphorus to calcium carbonate in the feed liquid is 1 (3-5).

According to an embodiment of the invention, the method further comprises: and S5, carrying out ion exchange treatment on the sodium tungstate concentrated material.

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 process flow diagram of a method for tungsten metallurgy in conjunction with silicon removal in accordance with an embodiment of the present invention;

FIG. 2 is a flow chart of a method for tungsten smelting in cooperation with silicon removal according to an embodiment of the invention.

Detailed Description

Embodiments of the present invention will be described in detail below, the embodiments described with reference to the drawings being illustrative, and the embodiments of the present invention will be described in detail below.

The method for tungsten smelting and silicon removal in coordination according to the embodiment of the invention is described below with reference to the accompanying drawings.

As shown in FIG. 1 and FIG. 2, the method for tungsten smelting synergistic silicon removal according to the embodiment of the invention comprises the following steps: s1, mixing the tungsten ore with a silicon removing agent, sodium phosphate and water to obtain first slurry. And S2, processing the first slurry under the conditions of preset temperature and preset pressure to obtain processed feed liquid. And S3, adding a phosphorus removing agent into the feed liquid to obtain a second slurry. And S4, filtering the second slurry to obtain tungsten slag and a sodium tungstate concentrated material. Wherein the silicon removing agent comprises sodium aluminate and magnesium oxide.

In other words, in the method for removing silicon by tungsten smelting in coordination, firstly, water can be added into the reaction tank, then stirring is started, and sodium aluminate, magnesium oxide, sodium phosphate and tungsten ore are sequentially added into the reaction tank and uniformly mixed to obtain the first slurry. The tungsten ore can be ball-milled before being added into the reaction tank, the tungsten ore is processed into small particles, the mixing efficiency of the tungsten ore and sodium aluminate, magnesium oxide and sodium phosphate is improved, and the tungsten ore can be uniformly mixed with the sodium aluminate, the magnesium oxide and the sodium phosphate.

And then, treating the first slurry by setting a certain temperature and pressure to obtain a feed liquid, wherein the temperature and the pressure can be high temperature and high pressure, the first slurry can be placed into an autoclave, a high temperature and high pressure environment can be formed in the autoclave, the first slurry is heated by high temperature steam, meanwhile, silicon dioxide in tungsten ore reacts with a silicon removing agent under the conditions of high temperature and high pressure to be converted into precipitate, and the precipitate enters tungsten slag solids in a subsequent filtering process, so that the silicon content in sodium tungstate filtrate is effectively reduced.

In the invention, a mixture of sodium aluminate and magnesium oxide is mainly used as a silica removing agent, wherein, the magnesium oxide can adopt industrial-grade magnesium oxide, and the sodium aluminate and the magnesium oxide can act synergistically in the process of removing silica. The sodium aluminate is used as the silicon removing agent, and has a certain silicon removing effect, but the sodium aluminate is expensive, so that the silicon removing cost of enterprises is increased. The magnesium oxide is low in price, but the silicon removal effect of the pure magnesium oxide is general, so that the silicon removal requirement of an enterprise in the tungsten smelting process is difficult to meet, and the quality of tungsten products is reduced.

In the invention, magnesium oxide is used for replacing part of sodium aluminate to form a mixture of sodium aluminate and magnesium oxide as a silica removing agent, so that the cost of the silica removing agent can be effectively reduced, and the sodium aluminate and magnesium oxide can form a synergistic effect in the silica removing process to further enhance the silica removing effect.

Specifically, in the actual silicon removal process by taking sodium aluminate and magnesium oxide as silicon removal agents, magnesium oxide is hydrated under the conditions of high temperature and high pressure to generate Mg²⁺，Mg²⁺Will react with SiO₃ ^2-Formation of insoluble MgSiO₃，MgSiO₃Can enter the solid phase. The sodium aluminate in the silica removing agent can play at least two roles, on one hand, the aluminum-containing compound can play a role in removing silica, and the aluminum-containing compound can reduce the pH value of the tungsten ore pulp to change silicate into silicic acid or sodium aluminosilicate. On the other hand, the aluminum-containing compound can act as a flocculant, and silicic acid, magnesium silicate and the like generated under the action of the aluminum-containing compound can flocculateThe aggregate together, so that the generated insoluble substance precipitation particles become larger, are easy to separate out from the ore pulp and are subjected to filter pressing in the subsequent flow, and a better silicon removal effect is achieved. Meanwhile, the tungsten ore mainly comprises calcium tungstate, calcium carbonate, calcium molybdate, molybdenum disulfide, calcium phosphate, arsenic, silicon and the like, and sodium aluminate and magnesium oxide only react with silicon dioxide, so that other impurities are not combined with aluminum and magnesium, and the impurity removal effect is influenced.

And (3) after the first slurry is subjected to high-temperature and high-pressure treatment, leading out the feed liquid, and adding a phosphorus removal agent into the feed liquid to remove phosphorus in the feed liquid to obtain a second slurry. The phosphorus removal agent can be calcium carbonate or other phosphorus removal agents, and compounds which can meet the phosphorus removal process are all within the protection scope of the application.

And finally, the second slurry can be placed into a filter press for filtering to obtain tungsten slag and sodium tungstate concentrated materials. Through detection, the silicon removal rate can reach 94 percent, even more than 99 percent by adopting the tungsten smelting synergistic silicon removal method, and a large amount of silicon removal cost is saved.

It should be noted that the existing tungsten ore generally contains 25 to 55 wt% of WO₃And 2 to 10 wt% of SiO₂. The autoclave used in the invention can adopt 15m³The design pressure of the autoclave can reach 1.6Mpa, the design temperature can reach 190 ℃, and the working medium can be sodium tungstate ore pulp and steam, so that the condition of tungsten smelting synergistic silicon removal is met.

Therefore, according to the method for removing silicon by tungsten smelting in a synergic manner, sodium aluminate and magnesium oxide are used as the silicon removing agent to remove silicon in a synergic manner, the sodium aluminate and the magnesium oxide do not react with other impurities to introduce new impurities, the sodium aluminate can also play a role of a flocculating agent to flocculate generated silicic acid, magnesium silicate and the like together, so that the generated insoluble substances are large in precipitate particles, are easy to separate out from slurry and filter out in a subsequent flow in a pressing manner, a better silicon removing effect can be achieved, the quality of tungsten products is improved, the magnesium oxide is low in price, the cost for removing silicon by tungsten can be effectively saved, and the production cost of tungsten is greatly reduced.

According to one embodiment of the invention, the mass ratio of the tungsten ore to the total amount of the silicon removing agent, the sodium phosphate and the water is 1 (0.3-3). The proportion can effectively remove silicon in the tungsten ore, so that the silicon removal rate reaches the industrial requirement, and the waste of auxiliary materials is not caused. Of course, it should be understood by those skilled in the art that the mass ratio of the tungsten ore to the total amount of the silicon removing agent, the sodium phosphate and the water can be adjusted according to actual needs, and detailed descriptions thereof are omitted in this application.

Optionally, in the silicon removing agent, the mass ratio of sodium aluminate to magnesium oxide is 1 (0.5-2). Therefore, under the proportion, the sodium aluminate and the magnesium oxide cooperatively remove silicon, on one hand, the sodium aluminate can react with certain silicon dioxide to remove silicon, on the other hand, the sodium aluminate flocculates precipitates generated by the reaction together, so that a good silicon removal effect can be achieved, and the silicon removal cost is reduced. The sodium aluminate can be prepared into a solution during the use process, and the concentration of aluminum ions in the sodium aluminate solution is approximately 30 g/l-40 g/l. Under the condition of the concentration, the sodium aluminate can play a good role in removing silicon, the pH value of the tungsten ore pulp can be reduced by the sodium aluminate or other aluminum-containing compounds formed in the first slurry, so that the silicate is changed into silicic acid or sodium aluminosilicate, and meanwhile, the sodium aluminate or other aluminum-containing compounds formed in the first slurry can play a role of a flocculating agent, so that the silicic acid, magnesium silicate and the like generated by the first slurry under the action of the aluminum-containing compounds can be flocculated together, and thus the generated insoluble substances are precipitated to be enlarged, are easy to be separated out from the ore pulp and are subjected to filter pressing in the subsequent flow, and. Meanwhile, the tungsten ore mainly comprises calcium tungstate, calcium carbonate, calcium molybdate, molybdenum disulfide, calcium phosphate, arsenic, silicon and the like, and the sodium aluminate and the magnesium oxide only react with silicon dioxide, so that the combination of other impurities, aluminum and magnesium is avoided, and the impurity removal effect is effectively enhanced.

In some embodiments of the invention, step S1 includes: s11, adding a first volume of water into the reaction tank and starting stirring. And S12, sequentially adding a silicon removing agent, sodium phosphate and tungsten ore into the reaction tank under the stirring state to obtain a first slurry.

That is, in step S1, first, 5m may be added to the reaction tank³-10m³Water and openAnd (4) stirring. Then, sodium aluminate, magnesium oxide, sodium phosphate and tungsten ore are added in sequence under the stirring state, so that the gradual and sufficient mixing of materials is realized, the obtained mixed solution is ensured to be more uniform, the problems of flocculation, agglomeration and the like are prevented, and the reaction in the next step is more sufficient. Of course, it will be understood by those skilled in the art that the volume of water to be added to the reaction tank may be specifically set according to the capacity of the reaction tank and the total amount of the materials to be added.

Optionally, in step S2, the preset temperature is 150 ℃ to 170 ℃. The preset pressure is 0.8MPa to 1.0MPa, and the time for treating the first slurry is 1.5h to 2 h.

In other words, the preset temperature in the autoclave can be realized by high-temperature steam, and the first slurry is subjected to heat preservation and pressure maintaining reaction for 1.5 to 2 hours under the conditions of high temperature and high pressure of 150 to 170 ℃ and 0.8 to 1.0MPa, so that magnesium oxide in the silicon removing agent can be hydrated to generate Mg²⁺，Mg²⁺Will react with SiO in the first slurry₃ ^2-Formation of insoluble MgSiO₃Finally, MgSiO₃Can enter the solid phase and be discharged, so that part of silicon in the first slurry is removed, the silicon removal pressure of sodium aluminate is reduced, and the silicon removal efficiency of tungsten ore is improved.

The specific temperature, pressure and holding time of the first slurry in the autoclave can be specifically set according to actual needs. The first slurry is fully reacted in the time, so that the full reaction of sodium aluminate, magnesium oxide and silicon dioxide can be realized, and a large amount of precipitates after the reaction can be gathered together, thereby achieving a good silicon removal effect.

According to one embodiment of the invention, the phosphorus removal agent is calcium carbonate, and the mass ratio of phosphorus to calcium carbonate in the feed liquid is 1 (3-5). The proportion can effectively remove phosphorus in the feed liquid without causing excessive use of calcium carbonate.

In some embodiments of the invention, the method for tungsten metallurgy with synergistic silicon removal further comprises: and S5, carrying out ion exchange treatment on the sodium tungstate concentrated material. As shown in fig. 1, ion exchange may be referred to simply as ion exchange. The purpose of the ion exchange treatment is to remove impurities and transform the sodium tungstate solution. Of course, the principles of ion exchange are understood and enabled by those skilled in the art and will not be described in detail in this application.

That is, as shown in fig. 1, tungsten ore is subjected to ball milling and then enters a slurry mixing step, water, a silicon removal agent and sodium phosphate are added in the slurry mixing process to form first slurry, the first slurry is subjected to pressure boiling to obtain feed liquid, calcium carbonate is added to perform phosphorus removal treatment on the feed liquid to obtain second slurry, the second slurry is filtered, tungsten slag and filtrate are obtained through separation, and finally the filtrate is subjected to ion exchange treatment.

In summary, the method for synergistic silicon removal in tungsten smelting according to the embodiment of the invention uses magnesium oxide and sodium aluminate as silicon removal agents, wherein the magnesium oxide is not only cheap, but also has the effect of silicon removal, and can play a good synergistic silicon removal effect together with the sodium aluminate. Magnesium oxide is adopted to replace part of sodium aluminate to remove silicon cooperatively, the content of silicon dioxide in the sodium tungstate concentrate is less than or equal to 300mg/l, and the silicon removal rate can reach more than 94 percent, so that the silicon removal rate can meet the industrial production requirement, and the cost of the silicon remover can be effectively reduced. The method has the advantages of simple process, convenient operation, continuous industrial production, good silicon removal effect, no introduction of new impurities, low silicon removal cost and the like.

The method for removing silicon by tungsten smelting in coordination with the embodiment of the invention is specifically described below with reference to specific embodiments.

Example 1

According to the method for removing silicon by tungsten smelting in a synergistic manner, the specific silicon removal process is as follows:

first, 6.5m was placed in a reaction vessel³Water, starting stirring, and sequentially adding 0.45m³Sodium aluminate solution (wherein Al³⁺With a concentration of 34.3g/l), 80kg of technical-grade magnesium oxide (MgO. gtoreq.90%) and 1100kg of sodium phosphate, followed by the addition of 5000kg of tungsten ore, WO₃Is 26.43 wt% SiO₂Was 2.23 wt%, and the resulting first slurry was fed to an autoclave after sufficient stirring. Introducing high-pressure steam into the autoclave for heating, and carrying out heat preservation and pressure maintaining reaction for 1.5h under the conditions that the temperature is 170 ℃ and the pressure is 0.97 MPa. After discharging, feeding the liquidCalcium carbonate is added to remove phosphorus (the mass ratio of the phosphorus content in the feed liquid to the calcium carbonate is 1:3), and second slurry is obtained. And filtering the second slurry by a filter press, and separating to obtain tungsten slag and sodium tungstate concentrated materials. Wherein the volume of the obtained sodium tungstate concentrate is 12.1m³Wherein SiO is₂The concentration is 69mg/l, the silicon removal rate is 99.24 percent, and the cost of the silicon removal agent is 555.39 yuan/ton.

Example 2

According to the method for removing silicon by tungsten smelting in a synergistic manner, the specific silicon removal process is as follows:

first, 6m was put into a reaction vessel³Water, starting stirring, and sequentially adding 0.45m³Sodium aluminate solution (wherein A)^l3+35.7g/l), 40kg of technical-grade magnesium oxide (MgO. gtoreq.90%) and 1200kg of sodium phosphate, followed by the addition of 5000kg of tungsten ore, WO₃Is 29.59 wt% SiO₂Was 2.29 wt%, and the resulting first slurry was fed to an autoclave after sufficient stirring. Introducing high-pressure steam into the autoclave for heating, and carrying out heat preservation and pressure maintaining reaction for 1.5h under the conditions that the temperature is 175 ℃ and the pressure is 0.95 MPa. And after discharging, adding calcium carbonate into the feed liquid to remove phosphorus (the mass ratio of the phosphorus content in the feed liquid to the calcium carbonate is 1:3) to obtain a second slurry. And filtering the second slurry by a filter press to obtain tungsten slag and sodium tungstate concentrated materials. Wherein the volume of the obtained sodium tungstate concentrate is 12.3m³Wherein SiO is₂The concentration is 430mg/l, the silicon removal rate is 95.58 percent, and the cost of the silicon removal agent is 526.34 yuan/ton.

Example 3

According to the method for removing silicon by tungsten smelting in a synergistic manner, the specific silicon removal process is as follows:

first, 7m was placed in a reaction vessel³Water, starting stirring, and sequentially adding 0.45m³Sodium aluminate solution (wherein Al³⁺Concentration of 38.7g/l), 20kg of technical grade magnesium oxide (MgO. gtoreq.90%) and 1250kg of sodium phosphate, and then 5000kg of tungsten ore, WO₃In an amount of 30.56 wt%, SiO₂Was 2.20 wt%, and the resulting first slurry was fed to an autoclave after sufficient stirring. Introducing high pressure steam into autoclave for heating, and maintaining at 173 deg.C and 0.97MPaAnd reacting for 1.5h under the condition of temperature and pressure. And after discharging, adding calcium carbonate into the feed liquid to remove phosphorus (the mass ratio of the phosphorus content in the feed liquid to the calcium carbonate is 1:3) to obtain a second slurry. And filtering the second slurry by a filter press to obtain tungsten slag and sodium tungstate concentrated materials. Wherein the volume of the obtained sodium tungstate concentrate is 12.6m³Wherein SiO is₂The concentration is 474mg/l, the silicon removal rate is 94.52 percent, and the cost of the silicon removal agent is 524.42 yuan/ton.

Example 4

According to the method for removing silicon by tungsten smelting in a synergistic manner, the specific silicon removal process is as follows:

first, 5.5m of the solution was placed in a reaction vessel³Water, start stirring, add 0.6m in turn³Sodium aluminate solution (wherein Al³⁺37.5g/l),120kg of technical-grade magnesium oxide (MgO. gtoreq.90%) and 1260kg of sodium phosphate, and then 3000kg of tungsten ore, WO₃In an amount of 57.13 wt%, SiO₂Is 7.86 wt%, and the resulting first slurry is fed to an autoclave after sufficient stirring. Introducing high-pressure steam into the autoclave for heating, and carrying out heat preservation and pressure maintaining reaction for 2 hours under the conditions that the temperature is 178 ℃ and the pressure is 0.87 MPa. And after discharging, adding calcium carbonate into the feed liquid to remove phosphorus (the mass ratio of the phosphorus content in the feed liquid to the calcium carbonate is 1:5) to obtain a second slurry. And filtering the second slurry by a filter press to obtain tungsten slag and sodium tungstate concentrated materials. Wherein the volume of the obtained sodium tungstate concentrate is 11.4m³Wherein, SiO₂The concentration is 180mg/l, the silicon removal rate is 99.11 percent, and the cost of the silicon removal agent is 633.88 yuan/ton.

Example 5

According to the method for removing silicon by tungsten smelting in a synergistic manner, the specific silicon removal process is as follows:

first, 5.5m of the solution was placed in a reaction vessel³Water, start stirring, add 0.6m in turn³Sodium aluminate solution (wherein Al³⁺With a concentration of 36.1g/l), 150kg of technical-grade magnesium oxide (MgO. gtoreq.90%) and 1350kg of sodium phosphate, followed by 2900kg of tungsten ore, WO₃In an amount of 60.24 wt%, SiO₂Was 9.71 wt%, and the resulting first slurry was fed to an autoclave after sufficient stirring. Introducing high-pressure steam into the autoclave for heating at the temperature of 1Keeping the temperature and pressure for reaction for 2h at 69 ℃ and under the pressure of 0.89 MPa. And after discharging, adding calcium carbonate into the feed liquid to remove phosphorus (the mass ratio of the phosphorus content in the feed liquid to the calcium carbonate is 1:4) to obtain a second slurry. And filtering the second slurry by a filter press to obtain tungsten slag and sodium tungstate concentrated materials. Wherein the volume of the obtained sodium tungstate concentrate is 11.3m³Wherein, SiO₂The concentration is 140mg/l, the silicon removal rate is 99.42 percent, and the cost of the silicon removal agent is 504.31 yuan/ton.

Comparative example 1

Silicon removal was carried out in the same manner as in example 1 except that only sodium aluminate was used for silicon removal and magnesium oxide was replaced with the same parts by weight of sodium aluminate, and the other conditions were the same as in example 1. The results show that the volume of the obtained sodium tungstate concentrate is 12.2m³Wherein, SiO₂The concentration is 48mg/l, the silicon removal rate is 99.47 percent, and the silicon removal cost is 1235.23 yuan/ton.

Comparative example 2

The silicon removal was carried out in the same manner as in example 1 except that silicon was removed only with magnesium oxide and sodium aluminate was replaced with the same weight part of magnesium oxide, and the other conditions were the same as in example 1. The results show that the volume of the obtained sodium tungstate concentrate is 11.6m³Wherein, SiO₂The concentration is 1820mg/l, the silicon removal rate is 81.07 percent, and the silicon removal cost is 156.95 yuan/ton.

Table 1 is a table of values of silicon removal rate and silicon removal cost obtained in example 1, comparative example 1 and comparative example two according to examples of the present invention.

TABLE 1

Therefore, as can be seen from table 1, under the same conditions, the silicon removal is performed only by using sodium aluminate, although a good silicon removal effect can be achieved, the cost is too high, and is about twice of the silicon removal cost by using sodium aluminate and magnesium oxide. And the silicon removal is carried out by only adopting magnesium oxide, although the silicon removal cost is low, the silicon removal effect is poor, and the silicon removal rate is below 90 percent, thus the industrial requirement is not met. In conclusion, when the sodium aluminate and the magnesium oxide are used for removing the silicon, the silicon removal rate is similar to that of the silicon removal rate only by using the sodium aluminate, the silicon removal rate can reach more than 99 percent, the silicon removal effect is good, and the silicon removal cost is low.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like 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 do not necessarily refer to the same embodiment or example.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.