阅读说明：本技术 一种节能高效的真空炉法制备脱氢电解锰的方法 (Energy-saving and efficient method for preparing dehydroelectrolytic manganese by vacuum furnace method ) 是由 王国宁 杨家冬 李佑稷 高峰 李绍东 刘汉勇 于 2020-04-02 设计创作，主要内容包括：本发明公开了一种节能高效的真空炉法制备脱氢电解锰的方法,本发明采用真空炉法对电解锰进行脱氢处理,可使电解锰中的氢含量达到H<0.001％以下,达到一些特殊情况下对电解金属锰的低氢要求且对脱氢温度、时间、真空度三个工艺关键参数进行了正交试验优化选择,得到了脱氢工艺表,可以根据需要采用不同的工艺条件生产不同氢含量的产品,实现高效、节能、成本更低的生产目标。(The invention discloses an energy-saving and efficient method for preparing dehydrogenized electrolytic manganese by a vacuum furnace method, which adopts the vacuum furnace method to perform dehydrogenization treatment on electrolytic manganese, so that the hydrogen content in the electrolytic manganese can reach below 0.001 percent, the low-hydrogen requirement of electrolytic manganese metal under some special conditions is met, and orthogonal test optimization selection is performed on three process key parameters of dehydrogenization temperature, time and vacuum degree, a dehydrogenization process table is obtained, products with different hydrogen contents can be produced by adopting different process conditions according to needs, and the production targets of high efficiency, energy saving and lower cost are realized.)

1. The energy-saving and efficient method for preparing the dehydroelectrolytic manganese by the vacuum furnace method is characterized by comprising the following steps of:

step one, filling electrolytic manganese for experiments into a vacuum furnace (1), vacuumizing, heating for dehydrogenation to obtain dehydroelectrolytic manganese, selecting different temperatures A, heating times B and vacuum degrees C to obtain the hydrogen content a of the dehydroelectrolytic manganese obtained under different process conditions, and making a dehydroprocess table, wherein the hydrogen content a of the dehydroelectrolytic manganese and the corresponding process conditions are sequentially arranged from small to large in the dehydroprocess table;

determining the maximum hydrogen content level b in the electrolytic manganese dehydrogenation according to the application of the electrolytic manganese dehydrogenation, selecting all process conditions with a being not more than b in a dehydrogenation process table as preselected process conditions, and selecting a process scheme with the lowest cost in the preselected process conditions as a final process condition;

and step three, filling the electrolytic manganese for production into a vacuum furnace (1), producing a dehydroelectrolytic manganese product according to the final selection process condition, and then cooling to below 150 ℃ and discharging to obtain the final product.

2. The energy-saving and efficient vacuum furnace method for preparing dehydroelectrolytic manganese according to claim 1, wherein a is less than 0.001%.

3. The energy-saving and efficient method for preparing the dehydroelectrolytic manganese by the vacuum furnace method according to claim 1, wherein A is 550-750 ℃, B is 1-3 h, and C is 350-50 pa.

4. The energy-saving and high-efficiency method for preparing the dehydroelectrolytic manganese by the vacuum furnace method according to claim 1, wherein the electrolytic manganese is loaded into the guide rail trolley (3) through the skip car (2), and the guide rail trolley (3) loads the electrolytic manganese into the vacuum furnace (1).

5. The energy-saving and high-efficiency method for preparing the dehydroelectrolytic manganese by using the vacuum furnace method as claimed in claim 1, wherein the vacuum furnace (1) is communicated with a plurality of vacuum pumps (4).

[ technical field ] A method for producing a semiconductor device

The invention relates to the field of metal smelting, in particular to an energy-saving and efficient method for preparing dehydroelectrolytic manganese by a vacuum furnace method.

[ background of the invention ]

Manganese is widely applied to industries such as steel and iron as an important metal element, a great part of the existing manganese production methods are electrolytic manganese metal, the existing electrolytic manganese metal product standards are continuously corrected along with the technical progress, and GB3418-82, YB/T051-93, YB/T051-2003 and YB/T051-2015 are mainly adopted in sequence, but indexes of hydrogen elements are not related in the standards, indexes of Mn, C, S, P, Si, Se, Fe, K, Na, Ca, Mg and other elements are specified in YB/T051-2015, and when special requirements on other chemical components are required by a supplier, the supplier and the demander negotiate additionally. Therefore, the content of hydrogen in the products produced by various enterprises at present is not specified.

1. Presence and effect of hydrogen in electrolytic manganese

Electrolytic manganese causes some hydrogen to be present in the product during the production process. Since manganese is a metal with high negative potential, since the U.S. mine administration proposed a diaphragm electrolysis method for producing manganese metal in 1935, the world always adopts a cathode liquid of a neutral MnSO4- (NH4)2SO4-H2O system to carry out diaphragm electrolysis, and the substances have certain adsorption crystallization entrainment in products. In the electrolytic manganese metal electrodeposition process, two competing electrochemical reactions simultaneously occur on the cathode.

Mn²⁺+2e＝Mn

2H⁺+2e＝H2↑

In addition, the newly formed manganese metal, especially the manganese metal which foams or even falls off the cathode plate due to the cause, reacts with water, Mn + H2O → MnOH + H₂

The metal manganese is electrolyzed and separated from the manganese sulfate aqueous solution, and because the cathode has two reactions of manganese separation and hydrogen separation, although a plurality of measures for inhibiting the hydrogen separation are taken in the actual operation process, the hydrogen separation reaction can not be completely avoided, and particularly, the hydrogen separation reaction is more serious under the conditions of summer production and higher temperature of an electrolytic bath. Therefore, the electrolytic manganese metal deposited at the cathode always entrains or adsorbs a certain amount of hydrogen, and the hydrogen content is generally 0.015% -0.020%.

However, hydrogen is harmful in metal materials, and the harm of hydrogen in steel is ① white spots, ② causes reduction of mechanical performance and welding performance, ③ causes hydrogen corrosion, ④ causes hydrogen embrittlement, ⑤ causes acid embrittlement, ⑤ causes bubbles and pinholes, so that hydrogen in metal manganese needs to be removed, no report is found at present on manganese dehydrogenation, temperature, time, vacuum degree and the like need to be controlled during dehydrogenation, uniform conditions are required for different products, resource waste is easily caused, manganese is easily damaged by high temperature for a long time, the quality of manganese is reduced, and higher equipment cost and operation cost are required for overhigh vacuum degree, so that the production cost is increased.

[ summary of the invention ]

In order to solve the problems, the invention discloses an energy-saving and efficient method for preparing dehydrogenized electrolytic manganese by a vacuum furnace method, which adopts the vacuum furnace method to perform dehydrogenization treatment on electrolytic manganese, so that the hydrogen content in the electrolytic manganese can reach below 0.001 percent, the low-hydrogen requirement of electrolytic manganese metal under some special conditions is met, and orthogonal test optimization selection is performed on three process key parameters of dehydrogenization temperature, time and vacuum degree, a dehydrogenization process table is obtained, products with different hydrogen contents can be produced by adopting different process conditions according to requirements, and the production targets of high efficiency, energy saving and lower cost are realized.

In order to achieve the purpose, the technical scheme of the invention is as follows:

an energy-saving and efficient method for preparing dehydroelectrolytic manganese by a vacuum furnace method comprises the following steps:

step one, filling electrolytic manganese for experiments into a vacuum furnace 1, vacuumizing, heating for dehydrogenation to obtain dehydroelectrolytic manganese, selecting different temperatures A, heating times B and vacuum degrees C to obtain the hydrogen content a of the dehydroelectrolytic manganese obtained under different process conditions, and making a dehydroprocess table, wherein the hydrogen content a of the dehydroelectrolytic manganese and the corresponding process conditions are sequentially arranged from small to large in the dehydroprocess table;

determining the maximum hydrogen content level b in the electrolytic manganese dehydrogenation according to the application of the electrolytic manganese dehydrogenation, selecting all process conditions with a being not more than b in a dehydrogenation process table as preselected process conditions, and selecting a process scheme with the lowest cost in the preselected process conditions as a final process condition;

and step three, filling the electrolytic manganese for production into the vacuum furnace 1, producing a dehydroelectrolytic manganese product according to the final selection process condition, and then cooling to below 150 ℃ and discharging to obtain the final product.

In a further improvement, a is less than 0.001%.

The further improvement is that A is 550-750 ℃, B is 1-3 h, and C is 350-50 pa.

In a further improvement, the electrolytic manganese is loaded into the guide rail trolley 3 through the skip car 2, and the guide rail trolley 3 loads the electrolytic manganese into the vacuum furnace 1.

In a further improvement, the vacuum furnace 1 is communicated with a plurality of vacuum pumps 4.

[ description of the drawings ]

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. The drawings in the following description are only some embodiments of the invention and other drawings may be derived by those skilled in the art without inventive effort, wherein:

FIG. 1 is a block diagram of the present invention.

[ detailed description ] embodiments

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. 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.

As shown in figure 1, the production system comprises a vacuum furnace 1, an electric heating pressure regulating and controlling system matched with the vacuum furnace, a filter dust remover 6, a two-stage vacuumizing and emptying system consisting of a vacuum pump 4 and a roots pump 5, a material loading trolley 2 and a guide rail trolley 3.

The key process parameters of the invention are as follows:

1. dehydrogenation temperature

The experiment adopts an accurate temperature control means, the dehydrogenation temperature is controlled to be between 550 and 750 ℃, the dehydrogenation temperature has great influence on the hydrogen content of the product, the dehydrogenation is incomplete if the temperature is low, and the sintering or melting phenomenon of manganese occurs when the temperature is too high, so that the effect is seriously influenced.

2. Time of heat preservation

The dehydrogenation holding time is directly related to the final completion degree of electrolytic manganese dehydrogenation. When the time is too short, the desorption and outward diffusion of the hydrogen-containing substance are not facilitated, and the hydrogen-containing substance is pumped out of the furnace body; if the time is too long, the manganese may be burned, the oxygen content of the product is too high, and the quality of the manganese is easily reduced. The reaction time was experimentally determined to be 1-3 hours.

3. Degree of vacuum in furnace

The proper vacuum conditions are also a key factor in determining the hydrogen content of the product. In the dehydrogenation process under the vacuum state, when the vacuum degree does not meet a certain requirement, the dehydrogenation speed is slower, the external air pumping speed of the vacuum pump is not high, the dehydrogenation effect is also influenced, the dehydrogenation is insufficient, the product quality is influenced, and the improvement of the vacuum degree means the investment on equipment and the further increase of the requirement on the process. The production system adopts a two-stage vacuum system, the front stage is formed by connecting two vacuum pumps in parallel, when only one vacuum pump is started, the system can reach 350Pa, the two vacuum pumps can reach 150Pa when the two vacuum pumps are operated in parallel, when the vacuum pump reaches the limit pumping effect, the roots pump is started again to carry out two-stage reinforced pumping, and the system can reach the maximum vacuum degree of 50 Pa. Therefore, the process can control the vacuum degree of the furnace atmosphere between 350pa and 50 pa.

2 Process parameter selection and optimization test for dehydrogenation effect (hydrogen content) of product

2.1 raw Material preparation and detection Instrument

2.1.1 electrolytic manganese metal sheet (DJMnD99.8%)

Each skip was loaded with 1.5 tonnes and the production (one test batch) was 3 tonnes for two skips per furnace run.

2.1.2 product hydrogen content detection equipment and method

An experimental instrument: ONH-3000 pulse infrared thermal conductance oxygen nitrogen hydrogen analyzer

The principle is as follows: the hydrogen content was measured by an inert gas pulse fusion thermal conductivity method (GB/T223.82-2007) which is suitable for the measurement of hydrogen over the whole range. Placing the prepared sample in a sample port, putting the sample into a degassed graphite crucible, melting the sample in a flowing atmosphere at a high temperature, separating the folded hydrogen from other gases, and detecting the separated hydrogen by using a thermal conductivity cell; and calculating the hydrogen content according to the change of the thermal conductivity. [4]

The instrument is provided with two independent infrared detection cells for respectively detecting hyperoxia and hypooxia and a thermal conductivity detection cell for detecting nitrogen and hydrogen in double ranges. The sample can be heated in a graphite crucible of a high-power pulse furnace to reach a high temperature of more than 3000 ℃, the instrument has the advantages of high sensitivity, good performance, wide measurement range, accurate and reliable analysis result and the like, is specially designed and manufactured for quickly and accurately measuring the contents of oxygen, nitrogen and hydrogen in a solid inorganic material, and can automatically realize switching from a low range to a high range in the analysis process.

Carrier gas: argon, helium and nitrogen with the purity of 99.9995 percent,

auxiliary materials: granular/rare earth copper oxide, alkali asbestos, anhydrous magnesium perchlorate, a tin sac, a graphite crucible and an electronic balance.

2.2 scheme design

2.2.1 Process control parameters

Orthogonal and optimized experimental scheme under three parameter (factor) conditions

Factor A is dehydrogenation temperature, wherein 550 ℃ is set as level 1, 650 ℃ is set as level 2, and 750 ℃ is set as level 3 according to the current production conditions. (levels 1, 2, 3 are referred to as lower temperature, moderate temperature, higher temperature, respectively)

The dehydrogenation time and the holding time under the high-temperature condition are respectively 1 hour, 2 hours and 3 hours, namely the level 1, 2 hours and 3 hours. (levels 1, 2, 3 are referred to as short, medium, and long, respectively)

Factor C is vacuum: according to the use mode and the combination control of the vacuum pump, 350Pa is set as a level 1, 150Pa is set as a level 2, and 50Pa is set as a level 3. (levels 1, 2, 3 are referred to as lower vacuum, medium vacuum, higher vacuum, respectively)

Orthogonality and optimization experiments an orthogonality table L9 of 3 factor 3 levels was chosen (3)³) The levels of the orthogonality tests are shown in table 1,

TABLE 1 orthogonal experiment factor horizon

The experiment was carried out for 9 batches of production and results were examined to obtain the dehydrogenation process table, see table 2 for details

TABLE 2 dehydrogenation Table

As can be seen from the results in the table, except for the use of A₁B₁C₁(lower temperature, shorter time and lower vacuum degree) the hydrogen content of the product produced by the process is higher than 10ppm, and the hydrogen content of the rest products is lower than 10ppm, wherein the best process conditions are as follows: moderate temperature (650 deg.C), moderate time (2 hr), high vacuum degree (50Pa), and low hydrogen content (5.6 ppm).

During production, the loss of energy consumption and vacuumizing energy consumption of the vacuum furnace, the loss of reaction time to the device, the production period and the like are judged to obtain the production cost and the production efficiency under different process conditions, and the lowest-cost or high-efficiency process capable of producing qualified products is selected according to the requirement for production, so that the purposes of saving energy and saving cost are achieved.

The invention has the following advantages:

1. the vacuum furnace method is adopted to carry out dehydrogenation treatment on the electrolytic manganese, so that the hydrogen content in the electrolytic manganese can reach less than 0.001 percent, and the low-hydrogen requirement on electrolytic manganese metal under some special conditions is met.

2. The dehydrogenation process carries out orthogonal test optimization selection on three process key parameters of dehydrogenation temperature, time and vacuum degree, the influence degree of each parameter on the dehydrogenation effect is obtained, the optimal value and optimal combination of each parameter are obtained, products with different hydrogen contents can be produced by adopting different process conditions, and the aims of high efficiency, energy conservation and lower cost are achieved.

While embodiments of the invention have been disclosed above, it is not limited to the applications set forth in the specification and the embodiments, which are fully applicable to various fields of endeavor for which the invention pertains, and further modifications may readily be made by those skilled in the art, it being understood that the invention is not limited to the details shown and described herein without departing from the general concept defined by the appended claims and their equivalents.