High-concentration liquid slow-release nitrogen fertilizer and preparation method thereof

Abstract

The invention discloses a high-concentration liquid slow-release nitrogen fertilizer and a preparation method thereof. The liquid slow-release nitrogen fertilizer is composed of 40-80 parts of urea, 18-50 parts of formaldehyde, 1-15 parts of an alkali compound, 1-15 parts of an amine compound, 1-15 parts of ammonia water, 0.001-1 part of a medium trace element-containing substance and 0.01-5 partof a biostimulant. The preparation method comprises the following steps: sequentially adding the components into a reaction kettle, and carrying out a series of reactions to obtain the high-concentration liquid slow-release nitrogen fertilizer. The liquid slow-release nitrogen fertilizer contains medium trace element substances and biostimulant, and can promote root growth and chlorophyll synthesis and improve crop quality; the fertilizer is directly sprayed on plant leaf surfaces and has the characteristics of quick effect, medium effect and slow effect so that the effective utilization rateof the nitrogen fertilizer is improved to 50 percent; the fertilizer can be randomly mixed with water and pesticides and is directly sprayed to crops so that the problem of non-uniform spreading of the traditional solid fertilizer is solved, and nitrogen loss and volatilization are greatly reduced. The defect of insufficient nitrogen source supply in the early stage of urea-formaldehyde resin is overcome, and the problems of high consumption, short lasting time, high loss rate, environmental pollution and the like of traditional urea are solved.

Description

technical field [0001] The invention relates to a high-concentration liquid slow-release nitrogen fertilizer and a preparation method thereof, in particular to a preparation method of a high-nitrogen content liquid slow-release nitrogen fertilizer. It belongs to the technical field of fertilizers. Background technique [0002] Fertilizer is an important factor affecting agricultural production, agricultural quality and agricultural health. It is the "grain" of various crops and food. my country uses 7% of the world's arable land to feed about 20% of the world's population. The role of fertilizer is indispensable. [0003] Nitrogen fertilizer, the first of the three elements of crop fertilization (nitrogen, phosphorus, and potassium), is one of the most important agricultural production inputs. It plays a very important role in increasing crop yield, soil fertility, and improving the quality of agricultural products. From the global average level, nitrogen fertilizer account...

AI Technical Summary

Problems solved by technology

There is a problem in this technical scheme There is a small amount of polymerized urea formaldehyde in the reaction product that affects storage stability

Patent US 2955390 describes the production of urea-form plant nutrition mixture from urea and UF-85 in the presence of potassium hydroxide alkalinity at a temperature of 90°C. The problem with this technical solution is that the prepared plant nutrition mixture product is usually The disadvantage of being basically unstable in a relatively short period of time, after a while there will be too much water separation, resulting in the instability of the entire solution system

Patent US3462256 describes the preparation of an aqueous solution of 80-90% partially reacted urea and formaldehyde by adding ammonia to the aqueous mixture of partially reacted urea and formaldehyde at 70°C. Only stable for 30 days at -25°C

It also contains a large amount of hexamethylenetetramine (HMT), and this technical solution has problems with poor slow-release effect and poor stability

The patent US4781749 has stated that 1.5-2.5 moles of formaldehyde are reacted in every mole of urea, and the initial molar ratio is lower than the initial molar ratio of 5 to 4 moles of formaldehyde per mole of urea, and the pH is kept near neutral conditions (6.9 -8.5), condensed UF chains have lower solubility than hydroxymethylated urea and can go on, there is a problem that results in extremely slow release, crops cannot use nitrogen source efficiently

Images