阅读说明：本技术 利用凝灰岩制备复合钾肥的方法及其产品和应用 (Method for preparing composite potassium fertilizer by utilizing tuff and product and application thereof ) 是由 黄涛 宋东平 刘龙飞 金俊勋 周璐璐 张树文 吴建勋 于 2020-05-19 设计创作，主要内容包括：本发明公开一种利用凝灰岩制备复合钾肥的方法,包括以下步骤：将凝灰岩进行研磨,过筛,得凝灰岩粉末；称取磷酸钠和凝灰岩粉末,混合,搅拌均匀得磷掺凝灰岩粉末；分别称量取草酸水溶液和磷掺凝灰岩粉末,混合搅拌,同时进行低温等离子体照射,得复合钾肥浆；称取活性炭粉末、磷石膏、复合钾肥浆,混合,搅拌均匀,密封条件下陈化,烘干,研磨,得复合钾肥。本发明还公开了该方法制备的复合钾肥及其应用。本发明方法充分利用了凝灰岩自身所含成分,制备过程无废渣产生且制备过程不涉及硫酸、硝酸、盐酸的使用,制备的复合钾肥可通过离子交换作用持续性地将钾元素释放到施肥土壤中,最高可获得14.58kg/m<Sup>2</Sup>红薯产量。(The invention discloses a method for preparing a composite potash fertilizer by utilizing tuff, which comprises the following steps: grinding tuff, and sieving to obtain tuff powder; weighing sodium phosphate and tuff powder, mixing, and stirring to obtain phosphorus-doped tuff powder; respectively weighing and taking an oxalic acid aqueous solution and phosphorus-doped tuff powder, mixing and stirring, and simultaneously carrying out low-temperature plasma irradiation to obtain composite potassium fertilizer slurry; weighing activated carbon powder, phosphogypsum and composite potassium fertilizer slurry, mixing, uniformly stirring, aging under a sealed condition, drying and grinding to obtain the composite potassium fertilizer. The invention also discloses the composite potash fertilizer prepared by the method and application thereof. The method of the invention makes full use of the components of tuff and has no waste in the preparation processSlag is generated, the use of sulfuric acid, nitric acid and hydrochloric acid is not involved in the preparation process, the prepared composite potash fertilizer can continuously release potassium elements into the fertilizing soil through ion exchange, and the maximum potassium element can be obtained to be 14.58kg/m 2 Sweet potato yield.)

1. A method for preparing a composite potassium fertilizer by utilizing tuff is characterized by comprising the following steps:

1) grinding tuff, and sieving with a 200-400 mesh sieve to obtain tuff powder;

2) weighing sodium phosphate and tuff powder, mixing, and stirring to obtain phosphorus-doped tuff powder;

3) respectively weighing and taking an oxalic acid aqueous solution and phosphorus-doped tuff powder, mixing and stirring, and simultaneously carrying out low-temperature plasma irradiation to obtain composite potassium fertilizer slurry;

4) weighing activated carbon powder, phosphogypsum and composite potassium fertilizer slurry, mixing, uniformly stirring, aging for 12-36 hours under a sealing condition, drying and grinding to obtain the composite potassium fertilizer.

2. The method for preparing the composite potassium fertilizer by using tuff as claimed in claim 1, wherein the mass ratio of the sodium phosphate in the step 2) to the tuff powder is 5-15: 100.

3. The method for preparing the composite potash fertilizer using tuff as claimed in claim 1, wherein the mass fraction of the oxalic acid aqueous solution in the step 3) is 5% -15%.

4. The method for preparing the composite potassium fertilizer by using tuff as claimed in claim 1, wherein the liquid-solid ratio of the oxalic acid aqueous solution and the phosphorus-doped tuff powder in the step 3) is 1-2: 1 mL/mg.

5. The method for preparing the composite potash fertilizer using tuff according to claim 1, wherein the stirring rotation speed of step 3) is 120-480 rpm.

6. The method for preparing the composite potash fertilizer using tuff according to claim 1, wherein the low temperature plasma irradiation action voltage of step 3) is 10-30 kV, and the irradiation time is 0.5-1.5 hours.

7. The method for preparing the composite potassium fertilizer from tuff according to claim 1, wherein the mass ratio of the activated carbon powder, the phosphogypsum and the composite potassium fertilizer slurry in the step 4) is (10-30): (5-15): 100.

8. the composite potash fertilizer prepared by the preparation method of any one of claims 1 to 7.

9. The use of the composite potash fertilizer of claim 8 in sweet potato planting.

Technical Field

The invention belongs to the technical field of resource utilization of tuff, and particularly relates to a method for preparing a composite potassium fertilizer by using tuff, and a product and application thereof.

Background

China is a traditional big agricultural country, and agricultural development is always an important link in economic construction of China. Although the cultivated land area is wide, the occupied amount of people is low in China. Meanwhile, due to over-cultivation, the fertility of the soil declines year by year, and fertilization is usually required to improve and maintain the fertility of the soil. At present, the self-supply rate of the potash fertilizer in China is about 50%, and a large amount of potash fertilizer still needs to be imported from abroad to make up for the production vacancy. The potash fertilizer mainly comprises potassium hydrogen phosphate, potassium chloride, potassium nitrate, potassium sulfate and the like. The production raw material of the potash fertilizer is usually a mineral containing potassium, and the content of potassium in the mineral needs to be more than 12%. The preparation process of the potash fertilizer comprises the processes of crushing, flotation, reverse flotation, evaporation, precipitation, separation, screening and the like. A large amount of sulfuric acid, nitric acid, hydrochloric acid and a flotation agent are needed in the production process of the potash fertilizer, the production process is easy to pollute the environment, and several tons of waste residues are generated when one ton of potash fertilizer is produced. Meanwhile, most of the produced potash fertilizers are single-variety fertilizers, and the effective utilization rate of the potash fertilizers is low. Currently, the dependence on high potassium content minerals and the environmental problems caused by the use of a large amount of inorganic acid in the production process of potash fertilizers have severely limited the expansion of the capacity of potash fertilizers.

In general, the development of production raw materials of potash fertilizers and the research and development of a method for preparing a composite potash fertilizer by effectively utilizing minerals (the content is lower than 10%) with low potassium content are effective ideas for solving the problem of insufficient supply of the conventional potash fertilizers. Meanwhile, the preparation process of the potash fertilizer needs to avoid the generation of waste residues and reduce the use of sulfuric acid, nitric acid and hydrochloric acid as much as possible. Tuff is a volcanic ash material with abundant mineral resources, and generally contains 4-8% of potassium. Tuff belongs to alkaline salt mine, and if the tuff is used as a raw material to prepare the potassium fertilizer by using a conventional process, more inorganic acid and a flotation machine are consumed, more acidic waste residues are generated, and the production cost and the disposal cost are increased rapidly. Therefore, the development of a new method for preparing the potash fertilizer by combining the characteristics of tuff is particularly critical to solve the problems.

Disclosure of Invention

The purpose of the invention is as follows: the invention aims to solve the technical problem of providing a method for preparing a composite potassium fertilizer by utilizing tuff.

The invention also aims to solve the technical problem of providing the composite potash fertilizer prepared by the preparation method and the application thereof.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows: the invention provides a method for preparing a composite potash fertilizer by utilizing tuff, which comprises the following steps:

1) grinding tuff, and sieving with a 200-400 mesh sieve to obtain tuff powder;

2) weighing sodium phosphate and tuff powder, mixing, and stirring to obtain phosphorus-doped tuff powder;

3) respectively weighing and taking an oxalic acid aqueous solution and phosphorus-doped tuff powder, mixing and stirring, and simultaneously carrying out low-temperature plasma irradiation to obtain composite potassium fertilizer slurry;

4) weighing activated carbon powder, phosphogypsum and composite potassium fertilizer slurry, mixing, uniformly stirring, aging for 12-36 hours under a sealing condition, drying and grinding to obtain the composite potassium fertilizer.

Wherein the mass ratio of the sodium phosphate and the tuff powder in the step 2) is 5-15: 100.

Wherein the mass fraction of the oxalic acid water solution in the step 3) is 5-15%.

Wherein the liquid-solid ratio of the oxalic acid water solution and the phosphorus-doped tuff powder in the step 3) is 1-2: 1 mL/mg.

Wherein the stirring speed in the step 3) is 120-480 rpm.

Wherein, the low-temperature plasma irradiation action voltage in the step 3) is 10-30 kV, and the irradiation time is 0.5-1.5 hours.

Wherein, the mass ratio of the activated carbon powder, the phosphogypsum and the composite potassium fertilizer slurry in the step 4) is (10-30) to (5-15) to 100.

The invention also comprises the composite potash fertilizer prepared by the preparation method.

The invention also comprises the application of the composite potassium fertilizer in sweet potato planting.

The reaction mechanism is as follows: grinding the tuff increases its contact area with other materials. In the low-temperature plasma irradiation process, high-energy electrons released by the high-voltage electrode end can react with water molecules to generate hydrogen radicals, hydroxyl radicals and hydrated electrons. The hydrogen free radicals and hydrated electrons can react with air and oxygen molecules in solution to generate active particles such as hydrogen ions, hydrogen peroxide, oxygen free radicals and the like. Meanwhile, due to the fact that energy level transition of particles is excited, a large amount of heat is released in the low-temperature plasma action process. After the oxalic acid aqueous solution and the phosphorus doped tuff powder are mixed, the oxalic acid can promote the release and dissolution of potassium ions in the tuff in the initial stage of low-temperature plasma irradiation, and then the oxalic acid reacts with hydroxyl radicals to generate carbon dioxide and water along with the increase of the hydroxyl radicals. Part of the carbon dioxide is released into the air and part of the carbon dioxide is hydrolyzed to produce carbonate and hydrogen ions. Under the strong oxidation action of hydroxide radical, oxygen free radical, hydrogen peroxide and other matter, the silicate and aluminosilicate in tuff are dissolved into liquid together with potassium ion. Under the action of thermal excitation and phosphate radical catalysis, the silicon salt and the aluminosilicate are hydrolyzed and polymerized to form the poly-silicon-aluminum colloid. Mixing activated carbon powder, phosphogypsum and composite potassium fertilizer slurry, and during stirring and ageing, firstly covering the activated carbon particles with a polysilicone aluminum colloid, and then reacting with the phosphogypsum to generate the ettringite mixed geopolymer. Phosphate radical and carbonate radical are combined with potassium ions absorbed in the geopolymer to form potassium phosphate, dipotassium hydrogen phosphate, potassium dihydrogen phosphate, potassium carbonate and potassium hydrogen carbonate, and the potassium phosphate, the dipotassium hydrogen phosphate, the potassium carbonate and the potassium hydrogen carbonate are covered or mixed on the surface or in pores of the geopolymer.

Has the advantages that: the invention has simple preparation process, wide and easily obtained sources of required raw materials. The method of the invention fully utilizes the components contained in tuff, no waste residue is generated in the preparation process, the preparation process does not involve the use of sulfuric acid, nitric acid and hydrochloric acid, the prepared composite potash fertilizer can continuously release the potassium element into the fertilizing soil through the ion exchange effect, and the highest potassium element can obtain 14.58kg/m²Sweet potato yield.

Drawings

FIG. 1 is a flow chart of the treatment method of the present invention.

Detailed Description

The invention is further described below with reference to the figures and examples.

The tuff powder of the present invention is from Xinyang Simutha technologies, Inc. of Henan. The tuff comprises the following components: SiO 2₂77.45％、Al₂O₃9.73％、CaO 0.78％、TiO₂1.45％、MgO 0.51％、Fe₂O₃1.23％、MnO 0.35％、V₂O₅0.46％、K₂O 7.83％、Na₂O 0.21％。

The phosphogypsum is obtained from Longquan phosphate fertilizer plants in Guizhou Xifeng county, and comprises the following components: SO (SO)₃48.91％、CaO 32.75％、SiO₂11.24％、P₂O₅4.68％、MgO 0.42％、Fe₂O₃0.31％、Al₂O₃0.24%, fluoride and others 1.54%.

Description of test plots: the test land is a farmland with a land area of 100m and comprising a constant-temperature Shajia creek town²(10m × 10m), the land is flat, the thickness of a plough layer is 25cm, the soil is brown soil, the soil is sticky, the soil texture is sticky, the soil is acidic (pH value is 5.8), and the soil fertility is middle-high.

Specification of test varieties: the variety to be tested is a starch type sweet potato variety (Nanshu 88).