Unlock instant, AI-driven research and patent intelligence for your innovation.

Core-shell structure slow/controlled release fertilizer and preparation method thereof

A core-shell structure, slow and controlled release fertilizer technology, applied in the direction of nitrogen fertilizer, fertilization device, fertilizer mixture, etc., can solve the problems of pollution, insolubility, waste of resources and the environment

Pending Publication Date: 2018-08-28
ZHENGZHOU GAOFU FERTILIZER CO LTD
View PDF4 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At present, the utilization rate of chemical fertilizers in my country is low, and the problems of waste of resources and environmental pollution are serious. Research and demonstrations in a large number of test bases have proved that coated slow-release fertilizers can greatly improve the utilization rate of fertilizer nutrients, which is conducive to saving fertilizer resources and protecting the environment. Ecological environment, ensuring the growth and development of crops
[0003] At present, the coating materials developed on the market include water-insoluble, slightly soluble or insoluble organic and inorganic materials. Although the slow and controlled release performance of fertilizers has been improved to varying degrees, there are still shortcomings that need to be improved.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Core-shell structure slow/controlled release fertilizer and preparation method thereof
  • Core-shell structure slow/controlled release fertilizer and preparation method thereof
  • Core-shell structure slow/controlled release fertilizer and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0021] Specifically, polyurea formaldehyde is mainly prepared by the following steps: mixing urea and formaldehyde in a molar ratio of 1-2.5:1, adjusting the pH value of the reaction system to 7.5-11.5, the temperature at 50°C-75°C, and then adjusting the pH Value to 2.5 ~ 5.5.

[0022] Compared with the traditional preparation method of polyurea-formaldehyde, the traditional preparation of polyurea-formaldehyde is to dissolve granular urea in water first, then add formaldehyde solution, heat the mixed solution to a certain temperature, adjust the pH value, and make it methylolate reaction. After the reaction is completed, the pH value and temperature are adjusted to allow polymerization to occur. The polyurea formaldehyde prepared by the traditional method is a suspension, and the polymerization reaction occurs completely in water. This preparation method has a water content as high as 70% or more after the polymerization reaction is completed, and part of the water needs t...

Embodiment 1

[0041] Mix granular urea and formaldehyde solution with a mass concentration of 37% in a molar ratio of 1.65:1 in the reactor, heat to 55°C, add sodium carbonate to adjust the pH value to 8.5, and generate methylol urea after 0.8 hours of reaction time . Then dilute sulfuric acid is added to adjust the pH value to 3.8 to obtain a raw material solution for coating. In advance, add granular urea with a diameter of about 2 mm into a drum coating machine (drum granulator) rotating at 14 rpm to preheat to 100 ° C, and then continuously spray the prepared coating raw material solution with a pH value of 3.8 to the surface of granular urea to make it solidify continuously to form a film. The spraying time is 15 minutes, and the slow-controlled release nitrogen fertilizer with a nitrogen content of 44% and a core-shell structure is prepared.

Embodiment 2

[0043] Fully mix molten urea and formaldehyde solution with a mass concentration of 37% in the reactor at a molar ratio of 1.75:1, adjust the temperature to 60°C, add dilute sodium hydroxide solution to adjust the pH value to 9.0, and generate hydroxyl after 0.6 hours of reaction time methyl urea. Then dilute sulfuric acid is added to adjust the pH value to 3.0 to obtain a raw material solution for coating. In advance, add fertilizer particles with a diameter of about 3.5mm and N, P and K contents of 17.2%, 18.5% and 12.3% respectively into the drum coating machine rotating at 14rpm to preheat to 110°C, and then put the prepared The coated raw material solution with a pH value of 3 is continuously sprayed onto the surface of the fertilizer particles as the core to make it continuously solidify and form a film, and the content of N, P and K in the slow-release fertilizer is 25%, 12% and 8% respectively. % core-shell structure slow-release fertilizer 100, spraying time 18 minut...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
diameteraaaaaaaaaa
Login to View More

Abstract

The invention provides a core-shell structure slow / controlled release fertilizer and a preparation method thereof and relates to the field of production of slow / controlled release fertilizers. The core-shell structure slow / controlled release fertilizer comprises a fertilizer granule core and a polyurea formaldehyde coating layer coated on the surface of the fertilizer granule core, wherein a molarratio of urea to formaldehyde in raw materials of polyurea formaldehyde is (1-2.5):1; the polyurea formaldehyde at least comprises polyurea formaldehyde containing 2-5 carbon atoms. Film structures of different carbon chain lengths can be formed by regulating reaction conditions and changing the molecular weight of the polyurea formaldehyde. The core-shell structure slow / controlled release fertilizer can achieve effects of controlling slow release of lots of nutrient elements such as nitrogen, phosphorus and potassium and controlling slow release of microelements such as calcium, magnesium, iron, zinc and the like, and meets requirements of different crops on nutrients.

Description

technical field [0001] The disclosure relates to the field of production of slow and controlled release fertilizers, and in particular to a slow and controlled release fertilizer with a core-shell structure and a preparation method thereof. Background technique [0002] Chemical fertilizers are an important means of production for agricultural development. With the continuous increase of human food demand, the amount of chemical fertilizers is also increasing. At present, the utilization rate of chemical fertilizers in my country is low, and the problems of waste of resources and environmental pollution are serious. Research and demonstrations in a large number of test bases have proved that coated slow-release fertilizers can greatly improve the utilization rate of fertilizer nutrients, which is conducive to saving fertilizer resources and protecting the environment. The ecological environment ensures the growth and development of crops. [0003] At present, the coating mat...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C05G3/08C05C9/02C05C9/00C05G3/90
CPCC05C9/00C05C9/02C05G5/30C05G3/90C05G5/37
Inventor 胡建民刘小勇胡锦哲万培坤白云涛胡书民
Owner ZHENGZHOU GAOFU FERTILIZER CO LTD