阅读说明：本技术 一种锰渣生产微量元素水溶肥料的方法 (Method for producing microelement water-soluble fertilizer from manganese slag ) 是由 杨晓红 薛希仕 常军 石维 于 2019-10-16 设计创作，主要内容包括：本发明属于工业废渣资源化利用领域,尤其是一种锰渣生产微量元素水溶肥料的方法,锰渣和硫酸充分反应,反应后加入中和剂进行中和反应,反应后固液分离,液体加入中和剂进行中和反应,中和反应后混合液进行固液分离,分离后液体加入氨基酸微量元素有机酸进行螯合反应,反应后进行固液分离,将分离后液体进行浓缩干燥,即可得到微量元素水溶肥料产品。本发明提供的方法,利用有机酸较强的鳌合能力将铜、锌、铁、锰等营养元素从锰渣中提取出来,生产微量元素水溶性肥料,可以大大降低土壤缺乏微量元素对人类健康带来的风险,符合国家对土壤保护及作物科学施肥的要求,扩大了锰渣的资源化利用的途径；而且生产工艺简单,成本较低。(The invention belongs to the field of resource utilization of industrial waste residues, and particularly relates to a method for producing a trace element water-soluble fertilizer by using manganese residues. According to the method provided by the invention, the nutrient elements such as copper, zinc, iron and manganese are extracted from the manganese slag by utilizing the strong chelating capacity of the organic acid to produce the trace element water-soluble fertilizer, so that the risk of the lack of the trace elements in the soil to human health can be greatly reduced, the national requirements on soil protection and scientific crop fertilization are met, and the resource utilization way of the manganese slag is expanded; and the production process is simple and the cost is low.)

1. The method for producing the trace element water-soluble fertilizer from the manganese slag is characterized by comprising the following steps of:

(1) reaction: manganese slag is crushed to 80-400 meshes and then mixed with sulfuric acid with the concentration of 10-50 w% according to a certain proportion, the mixture is placed in a reaction kettle, the temperature of the materials is controlled, and the reaction lasts for a period of time, so that a solution a is obtained;

(2) and (3) neutralization reaction: adding a neutralizing agent into the solution a for neutralization reaction, controlling the temperature and the pH of the material, and reacting for a certain time to obtain a solution b;

(3) and (3) activation reaction: adding organic acid into the solution a to perform a chelating reaction with trace elements in the system, controlling the temperature to react for a certain time, and performing solid-liquid separation to obtain a solid c and a liquid c.

(4) Concentrating and drying: and carrying out multi-effect concentration, drying and packaging on the liquid c to obtain the trace element water-soluble fertilizer.

2. The method for producing a trace-element water-soluble fertilizer from manganese slag according to claim 1, wherein in the step (1), the ratio of manganese slag to sulfuric acid is 1:0.5-8 (t: m)³)。

3. The method for producing the water-soluble fertilizer containing trace elements from manganese slag as claimed in claim 1, wherein in the step (1), the material temperature is controlled to be 20-120 ℃, and the reaction time is 5-120 min.

4. The method for producing a trace-element water-soluble fertilizer from manganese slag according to claim 1, wherein in the step (2), the ratio of the solution a to the neutralizing agent is 1:0.01-6 (m)³: t), the neutralizing agent is sodium hydroxide.

5. The method for producing the microelement water-soluble fertilizer by using the manganese slag as claimed in claim 1, wherein in the step (2), the material temperature is controlled to be 25-100 ℃, the pH value is controlled to be 1-7, and the reaction time is 15-90 min.

6. The method for producing a trace-element water-soluble fertilizer from manganese slag according to claim 1, wherein in step (3), the ratio of the solution b to the organic acid is 1:0.02-3 (m)³: t), the organic acid is one or more of citric acid, ethylene diamine tetraacetic acid, nitrilotriacetic acid, diethylene triamine pentaacetic acid, amino acid and humic acid or a mixture of more of the citric acid, the ethylene diamine tetraacetic acid, the nitrilotriacetic acid and the diethylene triamine pentaacetic acid.

7. The method for producing the water-soluble fertilizer containing trace elements from manganese slag as claimed in claim 1, wherein in the step (3), the temperature is controlled to be 20-90 ℃ and the reaction time is 10-150 min.

Technical Field

The invention belongs to the field of resource utilization of industrial waste residues, and particularly relates to a method for producing a trace element water-soluble fertilizer from manganese residues.

Background

According to statistics, the global manganese sulfate yield reaches 75 ten thousand tons per year at present. With the global economic return, the amount of basic raw materials is increasing. 20The global manganese sulfate yield in 15 years is 64.9 ten thousand tons, the global manganese sulfate yield in 2016 is 70.0 ten thousand tons, and the global manganese sulfate yield in 2017 is 75.4 ten thousand tons. The global yield of manganese sulfate in the last half year of 2018 is 40.5 ten thousand tons. In recent years, the consumption annual growth rate of manganese sulfate in western countries is about 7% -8%, the consumption growth rate of manganese sulfate in China is 10% on average, and in order to overcome the defects of low conversion rate, high energy consumption, high cost and the like of manganese sulfate produced by the traditional method, the technology of flue gas desulfurization by fully utilizing pyrolusite slurry of low-grade pyrolusite resources is paid more attention by the industry, namely the technology of flue gas desulfurization by utilizing composite ore slurry of pyrite and pyrolusite and SO-containing pyrolusite₂The flue gas is in reverse contact to realize the aim of desulfurization, and the temperature of the system is controlled to be 90-95 ℃ and the pH value is less than or equal to 2.0 in the reaction process; the manganese sulfate product can be obtained by removing impurities, concentrating and drying the generated liquid after the reaction, and because a large amount of reducing agents are used in the technology, a large amount of tailings can not be treated after the reaction, so that the environmental pollution is caused.

In recent 30 years, mankind has used a great deal of chemical fertilizer to increase the yield of various crops, and has achieved certain effect on the yield increase of crops. However, until now, the abuse of chemical fertilizers not only meets the bottleneck of plant yield increase, but also correspondingly represents more serious problems, because the abuse of chemical fertilizers for many years causes nutrition deficiency of the energetic and fertile soil under different conditions, a large amount of microorganisms are damaged, and trace elements are seriously lost. Statistically, more than 20 billion of the world's population is in a state of malnutrition today. Whereas more than 50% of the soil is deficient in trace elements, which directly results in reduced yield of crops and reduced quality of agricultural products. Over the past decades, the trace element content in crops has been decreasing, trace element deficiencies have had an adverse effect on human health, and increasing the trace element content in crops and soil by fertilization is the simplest and most effective method.

The manganese slag is rich in phosphorus and potassium, and medium and trace elements such as calcium, magnesium, sulfur, iron, manganese, zinc, copper, boron, molybdenum, chlorine, silicon, selenium and the like, and is a necessary nutrient element for crop production, so that the fertilizer efficiency of soil can be increased, and the growth of crops can be promoted. If the manganese slag can be processed into the trace element fertilizer, the effective recovery and comprehensive resource utilization of the manganese slag can be realized, the environmental pollution is reduced, and good economic benefit, environmental benefit and social benefit are generated.

The patent with the application number of CN201210478589.7 provides a method for recovering water-soluble manganese and magnesium from electrolytic manganese slag, which comprises the following steps: the method comprises the following steps: step one, mixing electrolytic manganese slag with water according to a certain proportion, stirring for a period of time, and filtering to obtain filtrate; adsorbing manganese in the obtained filtrate by using chelate resin, wherein magnesium flows out along with the effluent liquid; step three, eluting and regenerating the chelate resin adsorbed with manganese by using a solution containing 5-10% of sulfuric acid to obtain manganese sulfate eluent; and step four, adding ammonia water and ammonium carbonate into the obtained effluent liquid to precipitate magnesium, and filtering, washing and drying to obtain basic magnesium carbonate.

The patent with the application number of CN201610954693.7 provides a method for producing water-soluble silicon fertilizer by manganese slag, which comprises the following steps of alkalization, decomposition, neutralization, acid treatment and the like; the calcium method is to extract silicon element in manganese slag to produce water-soluble silicon fertilizer by adopting the processes of acid treatment, decomposition reaction, neutralization, alkalization and the like.

The method provided by the patent has the advantages that the utilization rate of the nutrient elements in the manganese slag is low, and the maximum utilization of the trace element resources in the manganese slag is not realized.

Disclosure of Invention

In order to solve the technical problems in the prior art, the invention provides a method for producing a trace element water-soluble fertilizer by using manganese slag, which is realized by the following technical scheme:

a method for producing a trace element water-soluble fertilizer from manganese slag comprises the following steps:

(1) reaction: manganese slag is crushed to 80-400 meshes and then mixed with sulfuric acid with the concentration of 10-50 w% according to a certain proportion, the mixture is placed in a reaction kettle, the temperature of the materials is controlled, and the reaction lasts for a period of time, so that a solution a is obtained;

(2) and (3) neutralization reaction: adding a neutralizing agent into the solution a for neutralization reaction, controlling the temperature and the pH of the material, and reacting for a certain time to obtain a solution b;

(3) and (3) activation reaction: adding organic acid into the solution a to perform a chelating reaction with trace elements in the system, controlling the temperature to react for a certain time, and performing solid-liquid separation to obtain a solid c and a liquid c.

(4) Concentrating and drying: and carrying out multi-effect concentration, drying and packaging on the liquid c to obtain the trace element water-soluble fertilizer.

Preferably, in the step (1), the ratio of the manganese slag to the sulfuric acid is 1:0.5-8 (t: m)³)。

Preferably, in the step (1), the material temperature is controlled to be 20-120 ℃, and the reaction time is 5-120 min.

Preferably, in the step (2), the ratio of the solution a to the neutralizing agent is 1:0.01-6 (m)³: t), the neutralizing agent is sodium hydroxide.

Preferably, in the step (2), the material temperature is controlled to be 25-100 ℃, the pH is controlled to be 1-7, and the reaction time is 15-90 min.

Preferably, in the step (3), the ratio of the solution b to the organic acid is 1:0.02-3 (m)³: t) the organic acid is one or more of citric acid, ethylene diamine tetraacetic acid, nitrilotriacetic acid, diethylene triamine pentaacetic acid, amino acid and humic acid or a mixture of more of the citric acid, the ethylene diamine tetraacetic acid, the nitrilotriacetic acid, the diethylene triamine pentaacetic acid, the amino acid and the humic acid,

preferably, in the step (3), the temperature is controlled to be 20-90 ℃, and the reaction time is 10-150 min.

In the step (4), the drying is microwave drying, and the multi-effect concentration is one of two-effect concentration, three-effect concentration, four-effect concentration and five-effect concentration.

The invention has the beneficial effects that:

the method provided by the invention is characterized in that reducing agents and pyrolusite in pyrolusite slurry flue gas desulfurization manganese slag are converted into soluble iron and manganese ions by utilizing sulfuric acid, and nutrient elements such as copper, zinc, iron and manganese are extracted from a system by adopting stronger chelating capacity of organic acid, so that chelated nutrition which is stable in structure and easy to absorb by crops is formed, and then the trace element water-soluble fertilizer is produced. The trace element water-soluble fertilizer produced by the invention has Mn content of 2.60% or more and iron content of 8.40% or more, and meets the related standards of the trace element water-soluble fertilizer NY 1428-2010; after the water-soluble fertilizer is applied to crops or soil, the risk of human health caused by the lack of trace elements in the soil can be greatly reduced, the national requirements on soil protection and scientific crop fertilization are met, and the resource utilization way of manganese slag is expanded; and the production process is simple and the cost is low.

Drawings

FIG. 1 is a schematic diagram of a process flow for producing a microelement water-soluble fertilizer from manganese slag.

Detailed Description

The technical solution of the present invention is further defined below with reference to the specific embodiments, but the scope of the claims is not limited to the description.

In the following examples, the chemical composition of manganese slag is shown in table 1:

TABLE 1

Composition (I)	SiO2	Al2O3	CaO	MnO	MgO	K2O	N-NH4	Fe2O3
									Content/%	45.67	10.20	6.30	4.80	2.10	1.12	1.20	24.30