CN114477294A - Method for treating oversize products of ammonium paratungstate - Google Patents
Method for treating oversize products of ammonium paratungstate Download PDFInfo
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- CN114477294A CN114477294A CN202210276179.8A CN202210276179A CN114477294A CN 114477294 A CN114477294 A CN 114477294A CN 202210276179 A CN202210276179 A CN 202210276179A CN 114477294 A CN114477294 A CN 114477294A
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- China
- Prior art keywords
- ammonium paratungstate
- oversize
- temperature
- products
- oversize products
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- XAYGUHUYDMLJJV-UHFFFAOYSA-Z decaazanium;dioxido(dioxo)tungsten;hydron;trioxotungsten Chemical compound [H+].[H+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.O=[W](=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O.[O-][W]([O-])(=O)=O XAYGUHUYDMLJJV-UHFFFAOYSA-Z 0.000 title claims abstract description 43
- 238000000034 method Methods 0.000 title claims abstract description 31
- 238000001354 calcination Methods 0.000 claims abstract description 27
- ZNOKGRXACCSDPY-UHFFFAOYSA-N tungsten trioxide Chemical compound O=[W](=O)=O ZNOKGRXACCSDPY-UHFFFAOYSA-N 0.000 claims description 54
- 239000000428 dust Substances 0.000 claims description 12
- 239000010419 fine particle Substances 0.000 claims description 6
- 239000000779 smoke Substances 0.000 claims description 6
- 239000002912 waste gas Substances 0.000 claims description 6
- 238000003672 processing method Methods 0.000 claims 2
- 239000013078 crystal Substances 0.000 abstract description 13
- QGLKJKCYBOYXKC-UHFFFAOYSA-N nonaoxidotritungsten Chemical compound O=[W]1(=O)O[W](=O)(=O)O[W](=O)(=O)O1 QGLKJKCYBOYXKC-UHFFFAOYSA-N 0.000 abstract description 8
- 229910001930 tungsten oxide Inorganic materials 0.000 abstract description 8
- 230000003647 oxidation Effects 0.000 abstract description 3
- 238000007254 oxidation reaction Methods 0.000 abstract description 3
- 239000000047 product Substances 0.000 description 40
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 9
- 238000001878 scanning electron micrograph Methods 0.000 description 8
- 239000000463 material Substances 0.000 description 7
- 239000002245 particle Substances 0.000 description 6
- 238000007873 sieving Methods 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 2
- 238000005054 agglomeration Methods 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 235000011114 ammonium hydroxide Nutrition 0.000 description 2
- 239000011362 coarse particle Substances 0.000 description 2
- 238000002425 crystallisation Methods 0.000 description 2
- 230000008025 crystallization Effects 0.000 description 2
- 238000011978 dissolution method Methods 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000003837 high-temperature calcination Methods 0.000 description 2
- 230000000704 physical effect Effects 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- XMVONEAAOPAGAO-UHFFFAOYSA-N sodium tungstate Chemical compound [Na+].[Na+].[O-][W]([O-])(=O)=O XMVONEAAOPAGAO-UHFFFAOYSA-N 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- 239000010937 tungsten Substances 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- 238000003723 Smelting Methods 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 230000002068 genetic effect Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000013067 intermediate product Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G41/00—Compounds of tungsten
- C01G41/02—Oxides; Hydroxides
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
Abstract
The invention relates to a method for treating oversize products of ammonium paratungstate, which is characterized in that the oversize products of ammonium paratungstate are subjected to two-belt temperature-controlled oxidation calcination in a rotary furnace, so that yellow tungsten oxide which can pass through a 70-mesh screen, has complete crystal form and meets the national standard can be directly obtained, and the method has the advantages of short treatment process, simplicity and convenience in operation, high direct yield, low cost and the like.
Description
Technical Field
The invention relates to the technical field of tungsten powder production, in particular to a method for treating oversize products of ammonium paratungstate.
Background
The hard alloy industry or the tungsten material processing industry have strict requirements on the granularity and the granularity distribution of tungsten powder, tungsten oxide is one of main raw materials for preparing the tungsten powder, the physical properties of the tungsten oxide directly influence the performance of the tungsten powder, upstream tungsten smelting enterprises are required to provide tungsten oxide raw materials with a certain granularity range, and the tungsten oxide is obtained by calcining ammonium paratungstate under the condition of introducing reducing or oxidizing atmosphere.
Since the national standard GB/T10116-2007 clearly requires that the ammonium paratungstate product can completely pass through a sieve with a pore diameter of 250um, in the crystallization and drying process for preparing ammonium paratungstate by using an ammonium tungstate solution, ammonium paratungstate crystals can be agglomerated into crystal agglomerations due to physical agglomeration, generally called as "coarse particles", the "coarse particles" need to be separated from normal products by sieving, collected and classified as oversize products, the chemical impurity content of the oversize products completely meets the national standard, and the direct yield is reduced due to the fact that the physical properties do not meet the standard. In the evaporation crystallization process and the drying process, 3% -7% of oversize products of ammonium paratungstate are often generated, and the oversize products of ammonium paratungstate need to be recycled, and the existing treatment methods mainly comprise the following three methods:
1. the mechanical crushing method can cause damage to crystal lattices and appearances, and brings genetic influence and increased mechanical loss to subsequent processing.
2. An alkali dissolution method, wherein ammonium paratungstate is dissolved in sodium hydroxide to obtain a sodium tungstate solution, and the sodium tungstate solution returns to the main flow; the method has the advantages of long process, high process loss rate and increased production cost.
3. The ammonia water redissolution method comprises the steps of dissolving ammonium paratungstate in ammonia water under a high pressure condition to obtain an ammonium tungstate solution, and returning the ammonium tungstate solution to a main flow; compared with the alkali dissolution method, the method has the advantages that the flow is relatively shortened, the method is the mainstream treatment method at present, but the problems of longer flow, low direct yield and increased production cost still exist.
Therefore, the development of a simple and easy-to-operate treatment method of the ammonium paratungstate oversize product with short flow and low cost is very significant.
Disclosure of Invention
The invention aims to provide a method for treating the oversize product of the ammonium paratungstate, which is simple and easy to operate, short in flow and low in cost.
The specific scheme is as follows:
the method for treating the ammonium paratungstate oversize products comprises the steps of calcining the ammonium paratungstate oversize products in an air atmosphere through a rotary calcining furnace, controlling the temperature of the rotary calcining furnace in two zones, controlling the temperature of one zone to be 250-400 ℃, controlling the temperature of the two zones to be 600-750 ℃, and calcining the ammonium paratungstate oversize products to obtain fine-particle tungsten trioxide products.
Furthermore, the rotating speed of the rotating furnace tube of the rotating calcining furnace is 3-20 r/min.
And further, air is introduced in the calcining process, the waste gas and the furnace burden move in a countercurrent mode, and the smoke dust is recovered at the feeding end through a dust collecting system and then is discharged.
Compared with the prior art, the method for treating the oversize products of the ammonium paratungstate has the following advantages: according to the method for treating the oversize product of the ammonium paratungstate, provided by the invention, the oversize product of the ammonium paratungstate is subjected to two-belt temperature-controlled oxidation calcination in the rotary furnace, so that the yellow tungsten oxide which can pass through a 70-mesh screen, has a complete crystal form and meets the national standard can be directly obtained, and the method has the advantages of short treatment process, simplicity and convenience in operation, high direct yield, low cost and the like.
Drawings
Figure 1 shows an SEM image of ammonium paratungstate oversize.
Fig. 2 shows an SEM image of the tungsten trioxide prepared in example 1.
Fig. 3 shows an SEM image of the tungsten trioxide prepared in example 2.
Fig. 4 shows an SEM image of the tungsten trioxide prepared in example 3.
Detailed Description
To further illustrate the various embodiments, the invention provides the accompanying drawings. The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the embodiments. Those skilled in the art will appreciate still other possible embodiments and advantages of the present invention with reference to these figures. Elements in the figures are not drawn to scale and like reference numerals are generally used to indicate like elements.
The invention will now be further described with reference to the accompanying drawings and detailed description.
The invention provides a method for treating oversize products of ammonium paratungstate, which comprises the steps of calcining the oversize products of ammonium paratungstate by a rotary calcining furnace, controlling the furnace temperature by two belts, controlling the furnace temperature by one belt to be 250-400 ℃, thermally decomposing coarse materials of ammonium paratungstate by low-temperature calcining by one belt, removing partial ammonia and crystal water, and cracking the coarse materials into fine particle products of ammonium metatungstate as a main component; the belt calcination time is 20 to 50 minutes. The temperature of the two-belt furnace is controlled to be 600-750 ℃, the intermediate product calcined at low temperature is made into a tungsten oxide finished product by the two-belt high-temperature calcination, the rotating speed of the rotary furnace tube is 3-20 r/min, the calcination time of the two-belt furnace tube is 20-50 minutes, air is introduced, waste gas and furnace burden move in a countercurrent mode, and smoke dust is recovered through a dust collection system at a feeding end and then is discharged. Calcining the ammonium paratungstate oversize product to obtain a fine-particle tungsten trioxide product, and screening the tungsten trioxide product through a 70-mesh sieve and then filling the tungsten trioxide product into a charging bucket.
Referring to fig. 1, fig. 1 is an SEM image (50 times) of an ammonium paratungstate oversize from which it can be seen that the morphology of the ammonium paratungstate oversize is mainly agglomerated crystals of ammonium paratungstate, which can be broken into fine particles by secondary calcination in a rotary kiln. In addition, the furnace temperature is controlled by two belts, one belt adopts low-temperature calcination, the materials can be crushed, the other belt adopts high-temperature calcination, the crystals can be further oxidized into tungsten trioxide, and the obtained product has fine particles and complete crystal form and meets the requirements of customers.
Example 1
And (2) calcining 6000kg of ammonium paratungstate oversize materials by a rotary calciner, wherein the furnace temperature is controlled in two zones, the furnace temperature of one zone is controlled to be 250 ℃, the furnace temperature of the two zones is controlled to be 600 ℃, the rotating speed of the rotary furnace tube is 3r/min, air is introduced, the waste gas and the furnace burden move in a countercurrent mode, and the smoke dust is recovered through a dust collection system at a feeding end and then is discharged. And (3) carrying out secondary calcination on the oversize product of the ammonium paratungstate to obtain fine tungsten trioxide particles, sieving the obtained tungsten trioxide product with a 70-mesh sieve, and then putting the tungsten trioxide particles into a charging bucket, wherein the tungsten trioxide oversize product is collected and weighed to be 131kg, and the direct yield of the ammonium paratungstate oversize product is calculated to be 97.8%. The SEM image (50 times) of the sieved tungsten trioxide is shown in figure 2, and the figure 2 shows that the tungsten trioxide has a complete crystal form and meets the national standard.
Example 2
And (2) calcining 6000kg of ammonium paratungstate oversize materials by a rotary calciner, wherein the furnace temperature is controlled in two zones, the furnace temperature of one zone is controlled to be 300 ℃, the furnace temperature of the two zones is controlled to be 650 ℃, the rotating speed of the rotary furnace tube is 10r/min, air is introduced, the waste gas and the furnace burden move in a countercurrent mode, and the smoke dust is recovered through a dust collection system at a feeding end and then is discharged. And (3) carrying out secondary calcination on the oversize product of the ammonium paratungstate to obtain fine tungsten trioxide particles, sieving the obtained tungsten trioxide product with a 70-mesh sieve, and then putting the tungsten trioxide particles into a charging bucket, wherein the tungsten trioxide oversize product is collected and weighed to be 89kg, and the direct yield of the ammonium paratungstate oversize product is calculated to be 98.5%. The SEM image (50 times) of the sieved tungsten trioxide is shown in figure 3, and the figure 3 shows that the tungsten trioxide has a complete crystal form and meets the national standard.
Example 3
And (2) calcining 6000kg of ammonium paratungstate oversize materials by a rotary calciner, wherein the furnace temperature is controlled in two zones, the furnace temperature of one zone is controlled to be 400 ℃, the furnace temperature of the two zones is controlled to be 750 ℃, the rotating speed of the rotary furnace tube is 20r/min, air is introduced, the waste gas and the furnace burden move in a countercurrent mode, and the smoke dust is recovered through a dust collection system at a feeding end and then is discharged. And (3) carrying out secondary calcination on the oversize product of the ammonium paratungstate to obtain fine tungsten trioxide particles, sieving the obtained tungsten trioxide product with a 70-mesh sieve, and then filling the tungsten trioxide particles into a charging bucket, wherein the tungsten trioxide oversize product is collected and weighed to be 267kg, and the direct yield of the ammonium paratungstate oversize product is calculated to be 95.6%. The SEM image (50 times) of the sieved tungsten trioxide is shown in figure 4, and the figure 4 shows that the tungsten trioxide has a complete crystal form and meets the national standard.
From the above examples 1-3, it can be seen that the method for treating oversize products of ammonium paratungstate provided by the present invention can directly obtain yellow tungsten oxide which can pass through a 70-mesh screen, has a complete crystal form and meets the national standard by performing two-belt temperature-controlled oxidation calcination on the oversize products of ammonium paratungstate in a rotary furnace, and has the advantages of short treatment process, simple operation, high direct yield, low cost, etc.
While the invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (3)
1. A method for treating oversize products of ammonium paratungstate is characterized by comprising the following steps: the method comprises the steps of calcining the ammonium paratungstate oversize products in a rotary calciner under the air atmosphere, controlling the temperature of the rotary calciner in two zones, controlling the temperature of one zone to be 250-400 ℃, controlling the temperature of the two zones to be 600-750 ℃, and calcining the ammonium paratungstate oversize products to obtain the fine-particle tungsten trioxide products.
2. The processing method according to claim 1, characterized in that: the rotating speed of a rotating furnace tube of the rotating calciner is 3-20 r/min.
3. The processing method according to claim 1, characterized in that: and air is introduced in the calcining process, the waste gas and the furnace burden move in a countercurrent manner, and the smoke dust is recovered at the feed end through a dust collecting system and then is discharged.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210276179.8A CN114477294A (en) | 2022-03-21 | 2022-03-21 | Method for treating oversize products of ammonium paratungstate |
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| CN202210276179.8A CN114477294A (en) | 2022-03-21 | 2022-03-21 | Method for treating oversize products of ammonium paratungstate |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114956184A (en) * | 2022-06-20 | 2022-08-30 | 厦门钨业股份有限公司 | Preparation method of low-Fischer yellow tungsten oxide |
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|---|---|---|---|---|
| US20120180600A1 (en) * | 2009-10-01 | 2012-07-19 | Japan New Metals Co., Ltd. | Method for Producing High-Purity Tungsten Powder |
| CN102649586A (en) * | 2012-05-24 | 2012-08-29 | 崇义章源钨业股份有限公司 | Method for dissolving ammonium paratungstate and/or tungsten oxide |
| CN108529680A (en) * | 2018-04-09 | 2018-09-14 | 洛阳栾川钼业集团股份有限公司 | A method of processing ammonium paratungstate oversize |
| CN108862391A (en) * | 2018-08-07 | 2018-11-23 | 厦门钨业股份有限公司 | A kind of low Fei Shi tungsten oxide and preparation method thereof |
| CN111333114A (en) * | 2020-03-17 | 2020-06-26 | 厦门钨业股份有限公司 | Method for preparing spherical ammonium paratungstate |
| CN113716610A (en) * | 2021-08-02 | 2021-11-30 | 崇义章源钨业股份有限公司 | Method for treating tungsten oxide furnace end powder and purple tungsten |
| CN113912125A (en) * | 2021-11-05 | 2022-01-11 | 赣州海盛钨钼集团有限公司 | Calcination process for preparing yellow tungsten oxide with high specific surface area and low residual ammonia |
-
2022
- 2022-03-21 CN CN202210276179.8A patent/CN114477294A/en active Pending
Patent Citations (7)
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| CN108529680A (en) * | 2018-04-09 | 2018-09-14 | 洛阳栾川钼业集团股份有限公司 | A method of processing ammonium paratungstate oversize |
| CN108862391A (en) * | 2018-08-07 | 2018-11-23 | 厦门钨业股份有限公司 | A kind of low Fei Shi tungsten oxide and preparation method thereof |
| CN111333114A (en) * | 2020-03-17 | 2020-06-26 | 厦门钨业股份有限公司 | Method for preparing spherical ammonium paratungstate |
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| CN113912125A (en) * | 2021-11-05 | 2022-01-11 | 赣州海盛钨钼集团有限公司 | Calcination process for preparing yellow tungsten oxide with high specific surface area and low residual ammonia |
Non-Patent Citations (1)
| Title |
|---|
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114956184A (en) * | 2022-06-20 | 2022-08-30 | 厦门钨业股份有限公司 | Preparation method of low-Fischer yellow tungsten oxide |
| CN114956184B (en) * | 2022-06-20 | 2023-11-21 | 厦门钨业股份有限公司 | Preparation method of low-Fisher yellow tungsten oxide |
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Application publication date: 20220513 |