阅读说明：本技术 一种冶炼制备钨钼铁合金的方法 (Method for preparing tungsten-molybdenum-iron alloy through smelting ) 是由 郭双华 高庆 谢承佳 张培培 于 2021-09-15 设计创作，主要内容包括：本案涉及冶炼制备钨钼铁合金的方法,将经过选矿富集得到的钨钼精矿、氧化钙、硅铁、铁屑、铝粒烘干研磨处理,然后按照一定质量比加入石墨坩埚中,于中频冶炼炉升温至550℃进行冶炼预处理,直至没有大量烟气排除；继续升温至1600-1750℃,熔炼60～120s,倒出冷却,既得产品。本发明制备过程简单,通过优化钨钼精矿中添加量的比例以及冶炼时长,对WO-(3)和Mo的回收率达到了90％以上。利用钨钼精矿通过一次投料、逐级升温的方式制得了钨钼合量合计＞55.00％的合金,可替代钨铁和钼铁用于钢的冶炼,避免分次添加或直接加入法带来的条件苛刻的问题。解决了钨钼共生矿钨钼难分离问题,实现该类资源的有效利用。(The scheme relates to a method for preparing a tungsten-molybdenum-iron alloy by smelting, which comprises the steps of drying and grinding tungsten-molybdenum concentrate obtained by mineral separation and enrichment, calcium oxide, ferrosilicon, scrap iron and aluminum particles, then adding the tungsten-molybdenum concentrate, the calcium oxide, the ferrosilicon, the scrap iron and the aluminum particles into a graphite crucible according to a certain mass ratio, and heating the mixture to 550 ℃ in a medium-frequency smelting furnace for smelting pretreatment until no large amount of flue gas is discharged; continuously heating to 1600-1750 ℃, smelting for 60-120 s, pouring out and cooling to obtain the product. The preparation method is simple in preparation process, and the addition amount ratio of the tungsten and molybdenum concentrates is optimizedDuration of smelting, for WO 3 The recovery rate of Mo reaches more than 90 percent. The tungsten-molybdenum concentrate is used for preparing the alloy with the tungsten-molybdenum total amount of more than 55.00% by one-time feeding and step-by-step heating, and the alloy can replace ferrotungsten and ferromolybdenum to be used for smelting steel, so that the problem of harsh conditions caused by a separate adding or direct adding method is avoided. The problem of difficult separation of tungsten and molybdenum in the tungsten-molybdenum paragenetic ore is solved, and the effective utilization of the resources is realized.)

1. The method for smelting and preparing the tungsten-molybdenum-iron alloy is characterized by comprising the following steps of: drying and grinding tungsten-molybdenum concentrate, calcium oxide, ferrosilicon, scrap iron and aluminum grains obtained by mineral separation and enrichment, and then according to the ratio of 100: 8-15: 10-20: 20-35: adding the mixture into a graphite crucible according to the mass ratio of 5-8, and heating the mixture to 550 ℃ in a medium-frequency smelting furnace for smelting pretreatment until no large amount of flue gas is discharged; continuously heating to 1600-1750 ℃, smelting for 60-120 s, pouring out and cooling to obtain the product.

2. The method for preparing the tungsten-molybdenum-iron alloy through smelting according to claim 1, wherein the tungsten content in the tungsten-molybdenum concentrate is 15-35%, the molybdenum content is 5-15%, the phosphorus content is less than 0.1%, the carbon content is less than 2%, the sulfur content is less than 0.5%, and the silicon content is less than 2%.

3. The method for preparing the tungsten-molybdenum-iron alloy by smelting as claimed in claim 1, wherein the temperature rise rate at 550 ℃ is 100 ℃/min; the temperature rise rate is 150 ℃/min when the temperature rises to 1600 ℃ and 1750 ℃.

4. The method for preparing the tungsten-molybdenum-iron alloy by smelting according to claim 1, wherein the particle size of the tungsten-molybdenum concentrate is less than 0.106 mm; 75-90% of the particles with the particle size of less than 0.074 mm.

5. The method for smelting and preparing the tungsten-molybdenum-iron alloy as claimed in claim 1, wherein the particle sizes of the calcium oxide and the ferrosilicon are both 0.106mm to 0.124 mm; the particle size of the scrap iron and the aluminum particles is less than 2 mm.

Technical Field

The invention relates to the technical field of alloy smelting, in particular to a method for smelting and preparing a tungsten-molybdenum-iron alloy.

Background

The tungsten ore in China mainly takes scheelite as a main material, mainly is sandstone-type and composite ore, and has the defects of low grade, low sorting recovery rate and the like. The scheelite is composed of calcium tungstate, and due to the geochemical characteristics of the scheelite, molybdenum can easily enter the scheelite in a similar form to form the tungsten-molybdenum paragenetic ore. The ore accounts for about 80 percent of the existing scheelite resources in China. The effective separation of the two elements is extremely difficult due to the extremely similar atomic radii, chemical valence states, chemical properties in aqueous solution, and the like of tungsten and molybdenum. The existing methods for separating tungsten and molybdenum, such as an extraction method, a precipitation method, an ion exchange method, a liquid membrane separation method and the like, have the problems of poor product quality, long process, high cost and the like to different degrees.

When molybdenum and tungsten are used as additives for steelmaking, ferromolybdenum and ferrotungsten are used as main raw materials, and the ferromolybdenum and the ferrotungsten are added into the steel smelting process according to a proper proportion to be smelted into corresponding steel grades. Obtaining ferromolybdenum and ferrotungsten, generally adopting a dressing and smelting process, enriching molybdenum concentrate and tungsten concentrate by dressing, roasting the molybdenum concentrate to generate molybdenum oxide, and smelting the molybdenum oxide to obtain ferromolybdenum; and the tungsten concentrate is directly smelted into ferrotungsten. In order to add ferromolybdenum and ferrotungsten to steel to obtain special steel or tungsten-containing molybdenum alloy steel, the ferromolybdenum and ferrotungsten need to be remelted, and the process is accompanied by large energy consumption and high production cost and loss of molybdenum and tungsten. In order to save energy, reduce cost and omit ferromolybdenum and ferrotungsten production procedures, molybdenum oxide and scheelite mixed ore or molybdenum oxide and tungsten concentrate can be adopted to replace part of ferromolybdenum and ferrotungsten. The smelting conditions are relatively harsh, and high-grade scheelite and molybdenum oxide are generally required to be selected.

For the resources, in order to avoid tungsten-molybdenum separation, the tungsten-molybdenum mixed product obtained by mineral processing is directly prepared into tungsten-molybdenum-iron alloy as an additive of special steel by combining the practical use of tungsten and molybdenum in steel, so that an effective application way is formed.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a method for preparing a tungsten-molybdenum-iron alloy by smelting a tungsten-molybdenum mixed product.

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

a method for preparing a tungsten-molybdenum-iron alloy by smelting comprises the following steps:

drying and grinding tungsten-molybdenum concentrate, calcium oxide, ferrosilicon, scrap iron and aluminum grains obtained by mineral separation and enrichment, and then according to the ratio of 100: 8-15: 10-20: 20-35: adding the mixture into a graphite crucible according to the mass ratio of 5-8, and heating the mixture to 550 ℃ in a medium-frequency smelting furnace for smelting pretreatment until no large amount of flue gas is discharged; continuously heating to 1600-1750 ℃, smelting for 60-120 s, pouring out and cooling to obtain the product.

Further preferably, the tungsten content in the tungsten-molybdenum concentrate is 15-35%, the molybdenum content is 5-15%, the phosphorus content is less than 0.1%, the carbon content is less than 2%, the sulfur content is less than 0.5%, and the silicon content is less than 2%.

Further preferably, the particle size of the tungsten-molybdenum concentrate is less than 0.106 mm; 75-90% of the particles with the particle size of less than 0.074 mm.

More preferably, the granularity of the calcium oxide and the ferrosilicon is 0.106 mm-0.124 mm; the particle size of the scrap iron and the aluminum particles is less than 2 mm.

Compared with the prior art, the invention has the beneficial effects that: the preparation method is simple in preparation process, and the proportion of the addition amount in the tungsten-molybdenum concentrate and the smelting duration are optimized to WO₃The recovery rate of Mo reaches more than 90 percent. The tungsten-molybdenum concentrate is used for preparing the alloy with the tungsten-molybdenum total amount of more than 55.00% by one-time feeding and step-by-step heating, and the alloy can replace ferrotungsten and ferromolybdenum to be used for smelting steel, so that the problem of harsh conditions caused by a separate adding or direct adding method is avoided. The problem that tungsten and molybdenum in the tungsten-molybdenum paragenetic ore are difficult to separate is solved, and the effective utilization of the resources is realized.

Detailed Description

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

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Examples

Firstly, the contents of main useful elements, water and other impurities in the mixed rough concentrate and WO in the raw material of the rough concentrate are found out₃25.71 percent of Mo, 10.56 percent of S and 0.04 percent of P. The pretreatment is carried out by an electrothermal blowing dry box, and the moisture of the material is controlled to be less than or equal to 1 percent. Controlling the granularity of the material by grinding equipment and grading equipment, and controlling the granularity of the tungsten-molybdenum bulk concentrate to be less than 0.106 mm; 75-90% of the particles with the particle size less than 0.074 mm; the granularity of calcium oxide and ferrosilicon is 0.106 mm-0.124 mm, and the granularity of iron filings and aluminium particles is less than 2 mm.

Example 1:

drying and grinding tungsten-molybdenum concentrate, calcium oxide, ferrosilicon, scrap iron and aluminum grains obtained by mineral separation and enrichment, and then according to the ratio of 100: 12: 18: 28: 6, adding the mixture into a graphite crucible, and heating the mixture to 550 ℃ in an intermediate frequency smelting furnace for smelting pretreatment until a large amount of flue gas is not discharged; continuously heating to 1600-1750 ℃, smelting for 60s, pouring out and cooling to obtain the product.

Example 2: the difference from example 1 is that the ferrosilicon mass is 20% of the coarse concentrate.

Example 3: the difference from the example 1 is that the quality of the ferrosilicon is 20 percent of that of the rough concentrate; the melting holding time was 80 s.

Example 4: the difference from the example 1 is that the quality of the ferrosilicon is 20 percent of that of the rough concentrate; the melting holding time was 100 s.

Example 5: the difference from the example 1 is that the quality of the ferrosilicon is 20 percent of that of the rough concentrate; the weight of the scrap iron is 30 percent of that of the rough concentrate.

Example 6: the difference from the example 1 is that the quality of the ferrosilicon is 20 percent of that of the rough concentrate; the weight of the scrap iron is 32 percent of that of the rough concentrate.

The composition analysis and recovery of the ferroalloys produced in examples 1-6 are shown in Table 1 below.

TABLE 1

Numbering	Mo％	WO3％	Si％	S％	P％	WO3The recovery rate is high	Recovery rate of Mo%
								Example 1	20.59	34.72	1.03	0.003	0.002	94.59	93.36
Example 2	21.12	34.89	1.34	0.003	0.002	95.84	94.01
								Example 3	21.63	35.77	1.17	0.002	0.002	96.36	95.25
Example 4	20.45	35.81	1.33	0.002	0.002	96.42	93.30
								Example 5	20.73	34.26	1.22	0.002	0.001	96.29	95.13
Example 6	20.28	33.73	1.09	0.002	0.001	96.08	95.07

As can be seen from Table 1, the indexes obtained under the conditions of example 3 are better, and the total tungsten and molybdenum content in the product is 57.40%. The Si content was 1.17% and the S, P content was low. Sufficient ferrosilicon can ensure the thoroughness of the reduction reaction of the materials, and the aim of improving the content of tungsten and molybdenum in the alloy is fulfilled. The excessive volatilization of molybdenum can be caused due to the overlong heat preservation time, and the recovery rate of the molybdenum is difficult to ensure.

While embodiments of the invention have been disclosed above, it is not limited to the applications listed in the description and the embodiments, which are fully applicable in all kinds of fields of application of the invention, and further modifications may readily be effected by those skilled in the art, so that the invention is not limited to the specific details without departing from the general concept defined by the claims and the scope of equivalents.