阅读说明：本技术 一种利用浓硫酸生产尿基复合肥的方法 (Method for producing urea-based compound fertilizer by using concentrated sulfuric acid ) 是由 付少华 刘松 于 2019-03-21 设计创作，主要内容包括：本发明公开了一种利用浓硫酸生产尿基复合肥的方法,属于肥料技术领域,包括以下步骤：在造粒机进料端加入浓硫酸、蒸汽与物料接触反应团粒造粒；浓硫酸与含尿基原料混合,首先与尿素反应生产硫酸脲,硫酸脲有很大的粘性,能很大程度提高造粒成球率,比来蒸汽转鼓造粒工艺产量提高30％,由于加入浓硫酸后,物料粘性增加,生产尿基复合肥时不用加入填料等,产品外观颜色变白,生产成本降低。本发明操作简单,不用加入填料,具有成本低廉、造粒成球率稿、产量高的特点,适合推广应用。(The invention discloses a method for producing a urea-based compound fertilizer by using concentrated sulfuric acid, which belongs to the technical field of fertilizers and comprises the following steps: adding concentrated sulfuric acid and steam at the feed end of a granulator to contact and react with the materials to granulate; the concentrated sulfuric acid is mixed with the urea-containing raw material, and the urea sulfate is firstly reacted with urea to produce urea sulfate, so that the urea sulfate has high viscosity, the granulation balling rate can be greatly improved, and the yield is improved by 30% compared with that of a steam drum granulation process. The invention has simple operation, does not need to add filler, has the characteristics of low cost, high granulation yield and high yield, and is suitable for popularization and application.)

1. A method for producing a urea-based compound fertilizer by using concentrated sulfuric acid is characterized by comprising the following steps: adding concentrated sulfuric acid and steam at the feed end of a granulator to contact and react with the materials to granulate; the concentrated sulfuric acid is mixed with the urea-containing raw material, and firstly reacts with urea to produce urea sulfate, the urea sulfate has great viscosity, and can improve granulation balling rate.

2. The method for producing a urea-based compound fertilizer by using concentrated sulfuric acid as claimed in claim 1, wherein the humidity of the granulated material is 2% -4%.

3. The method for producing a urea-based compound fertilizer using concentrated sulfuric acid as claimed in claim 1, wherein the granulation temperature is 60 ℃ to 90 ℃.

4. The method for producing a urea-based compound fertilizer by using concentrated sulfuric acid as claimed in claim 1, wherein the pH value of the material in the granulator is 5.5-6.5.

5. The method for producing a urea-based compound fertilizer by using concentrated sulfuric acid as claimed in claim 1, wherein the liquid-solid ratio of the materials in the granulator is as follows: (1-2): 10.

Technical Field

The invention belongs to the technical field of fertilizers, and relates to a method for producing a urea-based compound fertilizer by using concentrated sulfuric acid.

Background

From the viewpoint of the fertilizer production method, a compound fertilizer in which urea is used as a nitrogen source is called a urea-based compound fertilizer. The urea-base compound fertilizer is a high-concentration nitrogen-phosphorus-potassium multi-element compound fertilizer prepared by using urea as nitrogen source and using basic fertilizers of ammonium chloride, potassium sulfate, heavy calcium, ammonium phosphate and the like as raw materials and carrying out secondary processing, and the common production methods comprise an extrusion method, a granulation method, a slurry method, a melt method and the like. The conventional agglomeration method and slurry method are most commonly used, particularly high-concentration urea-based compound fertilizer, a certain amount of water is generally added into raw materials in the production process to meet the requirement of granulation, and drying equipment is arranged in the subsequent process, so that the particle strength of the product is influenced, and the investment cost of the device is increased.

Disclosure of Invention

The invention aims to provide a method for producing a urea-based compound fertilizer by using concentrated sulfuric acid, which has low cost, high granulation balling rate and high yield.

The specific technical scheme is as follows:

a method for producing a urea-based compound fertilizer by using concentrated sulfuric acid comprises the following steps:

adding concentrated sulfuric acid and steam at the feed end of a granulator to contact and react with the materials to granulate; the concentrated sulfuric acid is mixed with the urea-containing raw material, and the urea sulfate is firstly reacted with urea to produce urea sulfate, so that the urea sulfate has great viscosity, the granulation balling rate can be greatly improved, and the yield is improved by 30% compared with that of a steam drum granulation process.

Furthermore, the humidity of the granulated material is 2% -4%.

Further, the granulation temperature is 60 ℃ to 90 ℃.

Furthermore, the pH value of the materials in the granulator is 5.5-6.5.

Further, the liquid-solid ratio of the materials in the granulator is as follows: (1-2): 10.

compared with the prior art, the invention has the beneficial effects that:

the invention has simple operation, does not need to add filler, has the characteristics of low cost, high granulation yield and high yield, and is suitable for popularization and application.

Detailed Description

The technical solution of the present invention will be described in further detail with reference to specific examples.