阅读说明：本技术 硒化锌废料中回收硒的方法 (Method for recovering selenium from zinc selenide waste ) 是由 叶道明 陈应红 王波 何声华 刘春田 于 2020-12-16 设计创作，主要内容包括：本公开提供一种硒化锌废料中回收硒的方法,其包括步骤：步骤一：烘干,将硒化锌湿物料烘干,形成干物料；步骤二：破碎,物料颗粒小于3.5mm直接进行步骤三的工序,物料颗粒大于3.5mm进行破碎,破碎至能过3.5mm筛网,筛下物输送至回转窑的投料口；步骤三：投料,开启回转窑,当炉膛温度达到800～900℃时,将原料投入送料机内；步骤四：煅烧,控制回转窑炉膛温度850±50℃,转筒频率控制在10±2Hz进行煅烧；步骤五：煅烧结束后,设置转筒加热器温度使炉膛降温≤80℃时,停止转筒旋转,副产品在转筒出料口收集,产品二氧化硒半成品在产品柜收集,副产品送检测Se,当Se≥4％,返回投料,直至Se＜4％。本公开提供的回收方法工艺流程短,生产过程操作简单,硒回收率高。(The invention provides a method for recovering selenium from zinc selenide waste, which comprises the following steps: the method comprises the following steps: drying, namely drying the zinc selenide wet material to form a dry material; step two: crushing, wherein material particles are smaller than 3.5mm, the step three is directly carried out, the material particles are larger than 3.5mm, crushing is carried out until the material particles can pass through a 3.5mm screen, and undersize materials are conveyed to a feed inlet of the rotary kiln; step three: feeding, starting the rotary kiln, and feeding the raw materials into a feeder when the temperature of a hearth reaches 800-900 ℃; step four: calcining, wherein the temperature of a hearth of the rotary kiln is controlled to be 850 +/-50 ℃, and the frequency of a rotary drum is controlled to be 10 +/-2 Hz; step five: after calcining and sintering, setting the temperature of a rotary drum heater to reduce the temperature of a hearth to be less than or equal to 80 ℃, stopping the rotation of the rotary drum, collecting a byproduct at a discharge port of the rotary drum, collecting a semi-finished product of selenium dioxide in a product cabinet, detecting Se by the byproduct, and returning to feed when Se is more than or equal to 4% until Se is less than 4%. The recovery method provided by the disclosure has the advantages of short process flow, simple operation of the production process and high selenium recovery rate.)

1. A method for recovering selenium from zinc selenide waste is characterized by comprising the following steps:

the method comprises the following steps: drying, namely drying the zinc selenide wet material to form a dry material;

step two: crushing, wherein material particles are smaller than 3.5mm, the step three is directly carried out, the material particles are larger than 3.5mm, crushing is carried out until the material particles can pass through a 3.5mm screen, and undersize materials are conveyed to a feed inlet of the rotary kiln;

step three: feeding, starting the rotary kiln, and feeding the raw materials into a feeder when the temperature of a hearth reaches 800-900 ℃;

step four: calcining, wherein the temperature of a hearth of the rotary kiln is controlled to be 850 +/-50 ℃, and the frequency of a rotary drum is controlled to be 10 +/-2 Hz;

step five: after calcining and sintering, setting the temperature of a rotary drum heater to reduce the temperature of a hearth to be less than or equal to 80 ℃, stopping the rotation of the rotary drum, collecting a byproduct at a discharge port of the rotary drum, collecting a semi-finished product of selenium dioxide in a product cabinet, detecting the Se content in the byproduct, and returning to feed when the Se content is more than or equal to 4% until the Se content is less than 4%.

2. The method for recovering selenium from zinc selenide waste according to claim 1, wherein in the first step, the equipment for drying is a roasting furnace.

3. The method for recovering selenium from zinc selenide waste according to claim 1, wherein in the second step, the device used for crushing the materials is a coarse mill.

4. The method for recovering selenium from zinc selenide waste according to claim 1, wherein in the second step, the crushed material can pass through a 3.0mm screen.

5. The method for recovering selenium from zinc selenide waste according to claim 1, wherein in the fourth step, the temperature of the hearth of the rotary kiln is 850 ℃.

6. The method of claim 1, wherein in step four, the drum frequency is controlled at 10 Hz.

7. The method for recovering selenium from zinc selenide waste according to claim 1, wherein in the fourth step, the calcination time is 4-5 h.

8. The method of claim 1, wherein in step five the drum heater temperature is set at 0 ℃.

9. The method for recovering selenium from zinc selenide waste according to claim 1, wherein in step five, ICP measures the selenium content of the by-products.

Technical Field

The invention relates to the technical field of non-ferrous metal smelting, in particular to a method for recovering selenium from zinc selenide waste.

Background

The zinc selenide is a II-VI compound semiconductor material consisting of selenium and zinc, is a yellow transparent polycrystalline material, and has the crystal grain size of about 70 mu m and the light transmission range of 0.5-15 mu m. Due to excellent physicochemical properties, the zinc selenide crystal has important application prospects in the aspects of blue-light semiconductor light-emitting devices, nonlinear photoelectric devices, nuclear radiation detection devices and near ultraviolet-visible light detection devices, and the zinc selenide crystal basically has no impurity absorption and extremely low scattering loss. The absorption of light with the wavelength of 10.6 mu m is very small, so that the high-power CO production is realized₂The preferred materials for the optics of the laser system. In addition, the material is a material commonly used in different optical systems in the whole light-transmitting waveband, and particularly faces good development prospect in the laser processing equipment market and the infrared thermal imaging market.

With the steady increase of the market demand of zinc selenide infrared materials, how to extract and recover selenium from waste zinc selenide materials in the production and processing process in an environment-friendly and efficient manner makes full use of rare metal resources and reduces environmental pollution at the same time becomes a problem which needs to be solved urgently.

Disclosure of Invention

In view of the problems in the prior art, the present disclosure is directed to a method for recovering selenium from zinc selenide waste, which has a high recovery rate of selenium.

In order to achieve the above object, the present disclosure provides a method for recovering selenium from zinc selenide waste, comprising the steps of: the method comprises the following steps: drying, namely drying the zinc selenide wet material to form a dry material; step two: crushing, wherein material particles are smaller than 3.5mm, the step three is directly carried out, the material particles are larger than 3.5mm, crushing is carried out until the material particles can pass through a 3.5mm screen, and undersize materials are conveyed to a feed inlet of the rotary kiln; step three: feeding, starting the rotary kiln, and feeding the raw materials into a feeder when the temperature of a hearth reaches 800-900 ℃; step four: calcining, wherein the temperature of a hearth of the rotary kiln is controlled to be 850 +/-50 ℃, and the frequency of a rotary drum is controlled to be 10 +/-2 Hz; step five: after calcining and sintering, setting the temperature of a rotary drum heater to reduce the temperature of a hearth to be less than or equal to 80 ℃, stopping the rotation of the rotary drum, collecting a byproduct at a discharge port of the rotary drum, collecting a semi-finished product of selenium dioxide in a product cabinet, detecting the Se content in the byproduct, and returning to feed when the Se content is more than or equal to 4% until the Se content is less than 4%.

In some embodiments, in step one, the apparatus for drying is a roasting furnace.

In some embodiments, in step two, the apparatus used to break the material is a coarse mill.

In some embodiments, in step two, the crushed material can pass through a 3.0mm screen.

In some embodiments, in step four, the kiln hearth temperature of the rotary kiln is 850 ℃.

In some embodiments, in step four, the drum frequency is controlled at 10 Hz.

In some embodiments, in step four, the calcination time is 4 to 5 hours.

In some embodiments, in step five, the drum heater temperature is set to 0 ℃.

In some embodiments, in step five, the ICP measures the amount of selenium in the by-product.

The beneficial effects of this disclosure are as follows:

the method for recovering selenium from the zinc selenide waste has the advantages of short process flow, simple production process operation and high selenium recovery rate.

Detailed Description

The method for recovering selenium from zinc selenide waste according to the present disclosure is described in detail below.

The method for recovering selenium from the zinc selenide waste material comprises the following steps: the method comprises the following steps: drying, namely drying the zinc selenide wet material to form a dry material; step two: crushing, wherein material particles are smaller than 3.5mm, the step three is directly carried out, the material particles are larger than 3.5mm, crushing is carried out until the material particles can pass through a 3.5mm screen, and undersize materials are conveyed to a feed inlet of the rotary kiln; step three: feeding, starting the rotary kiln, and feeding the raw materials into a feeder when the temperature of a hearth reaches 800-900 ℃; step four: calcining, wherein the temperature of a hearth of the rotary kiln is controlled to be 850 +/-50 ℃, and the frequency of a rotary drum is controlled to be 10 +/-2 Hz; step five: after calcining and sintering, setting the temperature of a rotary drum heater to reduce the temperature of a hearth to be less than or equal to 80 ℃, stopping the rotation of the rotary drum, collecting a byproduct at a discharge port of the rotary drum, collecting a semi-finished product of selenium dioxide in a product cabinet, detecting the Se content in the byproduct, and returning to feed when the Se content is more than or equal to 4% until the Se content is less than 4%.

In the first step, the wet zinc selenide material is dried to form a dry material. And drying the zinc selenide wet material to form a dry material, which is beneficial to the crushing in the second step.

In some embodiments, in step one, the apparatus for drying is a roasting furnace. The roasting furnace is a machine which can obviously reduce the sintering temperature and greatly reduce the energy consumption. The method has great help for protecting environment and improving efficiency, and can also shorten time.

In step two, the material particles are smaller than 3.5mm, and preferably the material particles can pass through a 3.0mm screen. The material particles smaller than 3.5mm can be sufficiently calcined, and the smaller the material particles are, the more sufficient the calcination is.

In step two, the 3.5mm sieve is specially made, the material particles smaller than 3.5mm can be completely calcined, and the sieve is made to the manufacturer according to the size of the particle size.

In some embodiments, in step two, the apparatus used to break the material is a coarse mill. A coarse mill is a machine that pulverizes a large-sized solid raw material to a desired size.

In some embodiments, in the third step, when the temperature of the hearth reaches 800-900 ℃, the raw materials are put into the feeder. When the temperature reaches 800-900 ℃, feeding is beneficial to full reaction of materials, if the materials are fed in advance, the materials are accumulated, the reaction is incomplete, and the recovery rate of selenium is reduced.

In some embodiments, the kiln hearth temperature of the rotary kiln is controlled to 850 ± 50 ℃, preferably 850 ℃. The temperature is controlled within the range, which is beneficial to fully calcining the materials, and the boiling point of the selenium dioxide can not reach the melting point of the zinc oxide within the temperature range, so that the selenium dioxide and the zinc oxide can be automatically separated.

In some embodiments, the drum frequency is controlled at 10 ± 2Hz, preferably 10 Hz. If the frequency of the rotary drum is too high, the material calcining time is fast, the discharging is accelerated, selenium cannot be completely burnt out, and too much aggregate is accumulated in a too small hearth, so that the production is also influenced.

In step four, the high-temperature calcination oxidation mechanism is involved:

in some embodiments, in step four, the calcination time is 4 to 5 hours. Calcination is relatively complete within this time frame.

In step five, the main component of the byproduct is zinc oxide.

In the fifth step, the by-product is detected to be Se, and when Se is more than or equal to 4 percent, the material feeding is returned until Se is less than 4 percent. When the Se content in the by-product is less than 4 percent, the recovery is considered to be complete, and the material is not returned; and returning the material when the Se content in the byproduct is more than 4 percent.

In some embodiments, in step five, the ICP measures the amount of selenium in the by-product.

In the fifth step, the specific method for detecting the ICP is as follows: the first substep: firstly, crushing the byproducts, and uniformly mixing the samples; and a second substep: weighing about 0.2g of sample, dissolving with aqua regia, and fixing the volume to 200ml after the dissolution is finished; and a third substep: ICP is used according to the operation specification of the instrument, the normal state of the instrument is firstly ensured, under the condition that the instrument is normal, an external standard method is used for making a standard curve, and the concentration of the selenium standard curve is 0, 2, 4 and 8 mg/L; and a fourth substep: and (4) well preparing a standard curve, and detecting the selenium content in the solution treated in the step 2.

Finally, a test process is given:

example 1:

the method comprises the following steps: drying the zinc selenide wet material to form a dry material;

step two: directly carrying out the process of the third step when the material particles are smaller than 3.5mm, crushing the material particles larger than 3.5mm until the material particles can pass through a 3.5mm screen, and conveying undersize materials to a feed inlet of the rotary kiln;

step three: taking 500kg of dried and crushed zinc selenide waste with the metal selenium content of 54.7%, starting a rotary kiln, and when the temperature of a hearth reaches 850 ℃, putting the raw materials into a feeder for feeding;

step four: controlling the temperature of a hearth of the rotary kiln to be 850 ℃, controlling the frequency of a rotary drum to be 10Hz, and calcining for 4 hours;

step five: after calcining and sintering, setting the temperature of a rotary drum heater to reduce the temperature of a hearth to 80 ℃, adjusting a rotary drum frequency converter to reduce the rotating speed to 0, collecting 359.41kg of a byproduct at a discharge port of the rotary drum, collecting 369.14kg of a semi-finished product of selenium dioxide in a product cabinet, sending ICP of the byproduct to detect that Se is less than 2.7%, detecting that the content of selenium in the semi-finished product of selenium dioxide is 71%, and detecting the recovery rate of selenium to be 96.1%.

Example 2:

the method comprises the following steps: drying the zinc selenide wet material to form a dry material;

step two: directly carrying out the process of the third step when the material particles are smaller than 3.5mm, crushing the material particles larger than 3.5mm until the material particles can pass through a 3.5mm screen, and conveying undersize materials to a feed inlet of the rotary kiln;

step three: taking 500kg of dried and crushed zinc selenide waste with 55.1 percent of metallic selenium, starting a rotary kiln, and when the temperature of a hearth reaches 850 ℃, putting the raw materials into a feeder for feeding;

step four: controlling the temperature of a hearth of the rotary kiln to be 850 ℃, controlling the frequency of a rotary drum to be 10Hz, and calcining for 4.5 h;

step five: after calcining and sintering, setting the temperature of a rotary drum heater to reduce the temperature of a hearth to 80 ℃, adjusting a rotary drum frequency converter to reduce the rotating speed to 0, collecting a byproduct 360.42kg at a discharge port of the rotary drum, collecting a product 376.49kg of a semi-finished product of selenium dioxide in a product cabinet, detecting the ICP of the byproduct to be less than 3.4%, detecting the content of selenium in the semi-finished product of selenium dioxide to be 71%, and detecting the selenium recovery rate to be 97.3%.

Example 3:

the method comprises the following steps: drying the zinc selenide wet material to form a dry material;

step two: directly carrying out the process of the third step when the material particles are smaller than 3.5mm, crushing the material particles larger than 3.5mm until the material particles can pass through a 3.5mm screen, and conveying undersize materials to a feed inlet of the rotary kiln;

step three: : taking 500kg of dried and crushed zinc selenide waste with the metal selenium content of 54.9 percent, starting a rotary kiln, and when the temperature of a hearth reaches 850 ℃, putting the raw materials into a feeder for feeding;

step four: controlling the temperature of a hearth of the rotary kiln to be 850 ℃, and calcining for 5 hours;

step five: after calcining and sintering, setting the temperature of a rotary drum heater to reduce the temperature of a hearth to 80 ℃, adjusting a rotary drum frequency converter to reduce the rotating speed to 0, collecting 359.405kg of a byproduct at a discharge port of the rotary drum, collecting 373.58kg of a semi-finished product of selenium dioxide in a product cabinet, sending the detected Se of the byproduct ICP to a product cabinet to be less than 2.8%, detecting the content of selenium in the semi-finished product of selenium dioxide to be 71.2%, and detecting the selenium recovery rate to be 96.9%.

The above-disclosed features are not intended to limit the scope of practice of the present disclosure, and therefore, all equivalent variations that are described in the claims of the present disclosure are intended to be included within the scope of the claims of the present disclosure.