阅读说明：本技术 一种冶炼废水沉淀渣的资源回收处理方法 (Resource recovery processing method for smelting wastewater precipitation slag ) 是由 马致远 吕建芳 吕先谨 刘勇 刘牡丹 周吉奎 于 2020-04-30 设计创作，主要内容包括：本发明属于冶金行业固废处理技术领域,具体公开了一种冶炼废水沉淀渣的资源回收处理方法。该方法将钒冶炼废水沉淀渣破碎细磨后与碳酸钠混合,之后在微波环境中进行短时焙烧,得到焙烧渣,之后焙烧渣进行超声波快速水浸,固液分离得到含钒、钼浸出液。本发明提供的冶炼废水沉淀渣的资源回收处理方法,可以同时分离出钒和钼元素,且回收率高、纯度高,还有效缩短了沉淀渣的处理时间,提高了沉淀渣的处理量,不仅利于工业固废的无害化处理,还提供了一种新的钒、钼来源。(The invention belongs to the technical field of solid waste treatment in the metallurgical industry, and particularly discloses a resource recovery treatment method for smelting wastewater precipitation slag. The method comprises the steps of crushing and finely grinding the vanadium smelting wastewater precipitation slag, mixing the crushed and finely ground vanadium smelting wastewater precipitation slag with sodium carbonate, then carrying out short-time roasting in a microwave environment to obtain roasting slag, then carrying out ultrasonic rapid water leaching on the roasting slag, and carrying out solid-liquid separation to obtain leaching solution containing vanadium and molybdenum. The resource recovery processing method of the smelting wastewater precipitation slag provided by the invention can simultaneously separate vanadium and molybdenum elements, has high recovery rate and high purity, effectively shortens the processing time of the precipitation slag, improves the processing capacity of the precipitation slag, is beneficial to harmless treatment of industrial solid waste, and provides a new source of vanadium and molybdenum.)

1. A resource recovery processing method of vanadium smelting wastewater precipitation slag is characterized in that the vanadium smelting wastewater precipitation slag is crushed, finely ground, mixed with sodium carbonate and then roasted for a short time in a microwave environment to obtain roasting slag; and carrying out ultrasonic rapid water leaching on the roasting slag, and then carrying out solid-liquid separation to obtain leaching solution containing vanadium and molybdenum.

2. The resource recovery processing method of smelting wastewater precipitation slag according to claim 1, characterized in that the mass percentage of vanadate and molybdate in the leaching solution containing vanadium and molybdenum in the solution is more than or equal to 98%.

3. The method for resource recovery and treatment of smelting wastewater precipitation slag according to claim 1, characterized by comprising the steps of:

s1: crushing and finely grinding the vanadium smelting wastewater precipitation slag to obtain precipitation finely ground slag, mixing the precipitation finely ground slag with sodium carbonate, and then roasting in a microwave environment for a short time to obtain roasting slag;

s2: and (4) adding water into the roasting slag obtained in the step (S1) for size mixing, then carrying out ultrasonic rapid water leaching, and then carrying out solid-liquid separation to obtain leaching solution containing vanadium and molybdenum.

4. The resource recovery processing method of smelting wastewater precipitation slag according to any one of claims 1 to 3, characterized in that the microwave environment adopts the following microwave conditions: the microwave frequency is 900-3500 MHz, and the microwave power is 500-2000W.

5. The method for resource recovery of metallurgical off-water precipitation slag according to claim 4, wherein the short-time roasting time is controlled to 30-60 min.

6. The resource recovery processing method of smelting wastewater precipitation slag according to claim 5, characterized in that the ultrasonic conditions adopted by the ultrasonic rapid water immersion are as follows: the ultrasonic frequency is 25-40 kHz, the ultrasonic power is 400-1200W, and the water immersion treatment time is controlled to be 15-30 min.

7. The method for resource recovery of metallurgical off-water precipitation slag according to claim 6, wherein the roasting temperature for the short-time roasting is 400 to 700 ℃.

8. The method for resource recovery and treatment of the vanadium smelting wastewater precipitation slag according to claim 7, wherein the amount of the sodium carbonate is 20-50% of the weight of the vanadium smelting wastewater precipitation slag.

9. The method for resource recovery of smelting wastewater precipitation slag according to claim 3, wherein in step S2, the solid-to-liquid ratio of slurry obtained by adding water to the roasted slag and conducting slurry mixing is 0.10-0.50 g/mL.

10. The resource recovery treatment method of smelting wastewater precipitation slag according to claim 8 or 9, characterized in that the treatment temperature of the ultrasonic rapid water immersion is 60-80 ℃.

Technical Field

The invention relates to the technical field of solid waste treatment in the metallurgical industry, in particular to a resource recovery treatment method for precipitation slag generated after standing and precipitating smelting wastewater.

Background

The vanadium smelting generally adopts a roasting-leaching-precipitation process, a large amount of waste water is generated in the production process, such as precipitation mother liquor and vanadium extraction residual liquid, the waste water is subjected to standing precipitation to generate precipitation slag, and the precipitation slag contains valuable resources such as vanadium, molybdenum and the like and harmful substances such as chromium and the like.

With the rapid development of modern chemical industry at home and abroad, the demand of chemical raw materials such as vanadium, molybdenum and the like is increased year by year. The requirements of production development cannot be met by extracting vanadium, molybdenum and compounds thereof from ores only, so that the method has important strategic significance for recycling secondary resources containing vanadium and molybdenum. Therefore, it is necessary to recycle the vanadium smelting wastewater precipitation slag containing vanadium and molybdenum as resources.

The vanadium smelting wastewater precipitation slag is analyzed, mainly contains vanadium, molybdenum, iron, chromium, magnesium and the like, and the specific components are shown in the following table.

TABLE 1

Regarding the treatment of waste residues, the common methods at home and abroad are mainly divided into two types, namely pyrogenic treatment and wet treatment, wherein the pyrogenic treatment comprises an oxidizing roasting-alkali leaching method, and the wet treatment comprises an atmospheric acid leaching method, an atmospheric alkali leaching method and the like. The traditional pyrogenic process treatment process has the problems of high energy consumption, long time consumption, environmental pollution and the like, and can not meet the current environmental protection requirement gradually; the traditional wet treatment process mainly has the defects of poor raw material adaptability, metal dispersion, lower production efficiency and the like. At present, the vanadium smelting wastewater precipitation slag is treated by referring to the traditional pyrogenic process or wet process, and the defects of low resource recovery rate, high energy consumption and the like exist.

Disclosure of Invention

The invention mainly solves the technical problem of providing a resource recovery processing method of the smelting wastewater precipitation slag, which can realize the simultaneous recovery of vanadium and molybdenum in the vanadium smelting wastewater precipitation slag, and has short recovery processing time, high recovery rate and high product purity.

In order to solve the technical problems, the invention adopts the technical scheme that: a resource recovery processing method of vanadium smelting wastewater precipitation slag comprises the steps of firstly crushing and finely grinding the vanadium smelting wastewater precipitation slag, mixing the crushed and finely ground vanadium smelting wastewater precipitation slag with sodium carbonate, and then roasting the mixture for a short time in a microwave environment to obtain roasting slag; and carrying out ultrasonic rapid water leaching on the roasting slag, and then carrying out solid-liquid separation to obtain leaching solution containing vanadium and molybdenum.

Further, the mass percentage of vanadate and molybdate in the obtained leaching solution containing vanadium and molybdenum accounts for more than or equal to 98 percent of valuable metal compounds in the solution. The leaching solution basically does not contain impurities such as iron, chromium, magnesium and the like, and has high purity.

Further preferably, the resource recovery processing method of the vanadium smelting wastewater precipitation slag provided by the invention comprises the following steps:

s1: crushing and finely grinding the vanadium smelting wastewater precipitation slag, wherein the fine material with the ore grinding fineness of less than 0.074 mm accounts for more than 80% of the mass ratio to obtain precipitation fine grinding slag, mixing the precipitation fine grinding slag with sodium carbonate, and then roasting in a microwave environment for a short time to obtain roasting slag;

s2: and (4) adding water into the roasting slag obtained in the step (S1) for size mixing, then carrying out ultrasonic rapid water leaching, and then carrying out solid-liquid separation to obtain leaching solution containing vanadium and molybdenum.

Preferably, the microwave environment employs microwave conditions of: the microwave frequency is 900-3500 MHz, and the microwave power is 500-2000W.

Preferably, the short-time roasting time is controlled to be 30-60 min.

Preferably, the ultrasonic conditions for ultrasonic rapid water immersion are as follows: the ultrasonic frequency is 25-40 kHz, the ultrasonic power is 400-1200W, and the water immersion treatment time is controlled to be 15-30 min.

Preferably, the roasting temperature of the short-time roasting is 400-700 ℃.

Preferably, the amount of the sodium carbonate is 20-50% of the weight of the vanadium smelting wastewater precipitation slag.

Preferably, in step S2, the solid-to-liquid ratio of the slurry obtained by adding water to the roasted slag and mixing the slurry is 0.10 to 0.50 g/mL.

Preferably, the processing temperature of the ultrasonic rapid water immersion is 60-80 ℃.

The vanadium smelting wastewater precipitation slag treated by the method is the precipitation slag generated after the vanadium smelting wastewater is treated by a chemical-coagulation combined process. The chemical-coagulation combined treatment process is a treatment method of vanadium smelting waste water, and its technological process includes 4 procedures of sulfurization, acidification to remove molybdenum, reduction, neutralization and precipitation of chromium and vanadium, in which the vanadium in the produced precipitation slag mainly exists in the form of vanadium oxide, and the molybdenum mainly exists in the form of molybdenum sulfide. Because vanadium and molybdenum are precipitated in a segmented mode and exist in different forms, a solvent which can effectively react with the vanadium and the molybdenum needs to be selected to realize the joint recovery of the vanadium and the molybdenum. The research of the invention finds that the effective co-recovery of vanadium and molybdenum can be realized by adopting sodium carbonate.

It has also been found in research that the amount of heat generated by a substance in a microwave field is strongly related to the type of substance and its dielectric properties, i.e. microwaves have the property of selectively heating certain substances. The inventor finds that vanadium and molybdenum in the vanadium smelting wastewater precipitation slag belong to strong microwave absorbing substances, and compared with elements such as iron, chromium and the like, compounds of vanadium and molybdenum have high sensitivity to microwaves. When the vanadium and molybdenum compounds in the vanadium smelting wastewater precipitation slag are roasted in a microwave field, the vanadium and molybdenum compounds in the vanadium smelting wastewater precipitation slag can quickly reach higher temperature. Therefore, based on the above discovery, the microwave selective treatment of vanadium and molybdenum can be realized by roasting the vanadium smelting wastewater precipitation slag under the microwave condition. The added sodium carbonate can also play a role in microwave activation, because the sodium carbonate also belongs to a strong microwave absorbing substance and can be rapidly heated in a microwave field.

The method comprises the steps of crushing and finely grinding the vanadium smelting wastewater precipitation slag to a certain fineness, and then mixing the vanadium smelting wastewater precipitation slag with sodium carbonateAnd (3) combining, and then roasting in a microwave environment, wherein vanadium and molybdenum compounds in the vanadium smelting wastewater precipitation slag are rapidly heated in a microwave field, and the vanadium and molybdenum compounds in the precipitation slag are rapidly converted into vanadate and molybdate which are easy to dissolve, so that the roasting purpose is achieved. Meanwhile, due to the characteristics of the microwave, a large number of cracks can be formed in the roasting process of the materials in the microwave field, and the contact surface between the air atmosphere and the materials is greatly increased, so that the roasting reaction can be promoted, and the roasting efficiency is improved. Because vanadium and molybdenum in the vanadium smelting wastewater precipitation slag belong to strong microwave absorbing substances, the vanadium smelting wastewater precipitation slag has high microwave sensitivity and can quickly realize the roasting purpose, the roasting time is obviously shortened, and the energy consumption is obviously reduced; and other impurity elements, e.g. Fe, Cr or Fe₂O₃And Cr₂O₃The water-soluble organic silicon dioxide is in a form which can not be dissolved in water, so that the organic silicon dioxide does not enter the leaching solution during subsequent water leaching treatment, and the purity of the leaching solution is improved.

The roasting slag obtained after microwave roasting treatment is directly subjected to water leaching, and because vanadium and molybdenum in the precipitation slag are converted into water-soluble vanadate and molybdate, the vanadium and molybdenum can be directly leached into a water phase without adding acid or alkali for leaching. When roasting is carried out in a microwave field in the prior art, the caking phenomenon is easily caused due to the excessively high material heating speed, and the leaching process can be carried out only after grinding is usually carried out, so that the processes are multiple, the flow is long, and the energy consumption is increased. The invention effectively solves the problem by adopting ultrasonic waves, can effectively solve the problem of material agglomeration and caking due to the mechanical effect, the thermal effect and the cavitation effect of the ultrasonic waves, and finds that the leaching efficiency is also improved, the leaching time is obviously shortened, and the water leaching treatment time can be completed only by 15-30 min.

According to the resource recovery processing method of the vanadium smelting wastewater precipitation slag, provided by the invention, microwaves are adopted for roasting and dissolving out according to the composition characteristics of the vanadium smelting wastewater precipitation slag, then ultrasonic water immersion is carried out, materials subjected to microwave treatment have certain structural changes, the leaching effect is better under the action of ultrasonic waves, the reaction is quicker, the time is shortened, and the leaching efficiency is greatly improved. Experiments prove that by adopting the method disclosed by the invention, most of vanadium and molybdenum in the precipitation slag can be leached, and the recovery rates of the vanadium and the molybdenum can respectively reach 95-99% and 96-99%. The leaching solution has high purity, mainly comprises vanadium and molybdenum, and the mass percentage of vanadate and molybdate in the valuable metal compounds in the solution is more than or equal to 98 percent. The content of vanadium and molybdenum in leached slag is less than 1 percent. The leaching slag mainly contains iron, chromium and magnesium, and valuable metals are enriched, so that the leaching slag is convenient to recycle. The obtained leachate has high purity, the subsequent purification process of vanadium and molybdenum is greatly simplified, and for example, ammonium metavanadate and ammonium molybdate with high purity can be directly obtained by a step-by-step precipitation (ammonium salt vanadium precipitation + acidification molybdenum precipitation) method.

The resource recovery processing method of the smelting wastewater precipitation slag provided by the invention realizes the simultaneous recovery of vanadium and molybdenum in the vanadium smelting wastewater precipitation slag, and provides a new source of vanadium and molybdenum chemical raw materials. In addition, the recovery treatment method has low production cost, low labor intensity and short treatment time, improves the treatment capacity of the precipitation slag, is more favorable for promoting the resource treatment of the precipitation slag of the vanadium smelting wastewater, and realizes the energy conservation, emission reduction and green production of the vanadium industry.

Detailed Description

The technical solution of the present invention will be described in detail by specific examples.