Preparation method for nitrate urea-formaldehyde fertilizer

Abstract

The invention discloses a preparation method for nitrate urea-formaldehyde fertilizer. The method comprises the following steps of: adding hot water in a kettle, rising temperature to 65 DEG C, adding urea, stirring and dissolving, adjusting PH value to 8.6 to 8.8 through 20% NaOH, adding formaldehyde with a weight ratio between formaldehyde and urea of 1:1.8, rising temperature to 85 DEG C, keeping temperature for 20 to 30 min, adding nitrate nitrogenous fertilizer in a backing material of a granulator according to a calculated formula NPK raw materials at a constant temperature about 80 DEG C, dehydrating to make grains, drying, cooling and screening to acquire the finished product. The nitrate urea-formaldehyde fertilizer contains urea, formaldehyde, monoammonium phosphate, potassium sulfate and ammonium nitrate. The invention has the advantages of convenient preparation, low cost, high nitrogen content, quick-acting and slow-acting functions of supplying nitrogen element, decreased pouring and volatilized loss, promoted use ratio, and the like.

Description

technical field [0001] The invention belongs to the technical field of agricultural production of chemical fertilizers, in particular to a preparation method of nitrate urea formaldehyde fertilizer. Background technique [0002] Urea-formaldehyde fertilizer refers to urea-formaldehyde slow-release nitrogen fertilizer, also known as MU, UF. It is mainly to control the slow release of nitrogen, prevent the loss of nitrogen fertilizer, and improve the efficiency of nitrogen fertilizer. [0003] Urea-formaldehyde fertilizer is a slow-release fertilizer manufactured by chemical synthesis, which is produced by the condensation reaction of urea and formaldehyde aqueous solution. [0004] Urea-formaldehyde was the pioneer product of slow-release fertilizers, commercially produced in 1955. Internationally, Japan, the United States, Europe, etc. produce two types of urea-formaldehyde and urea-formaldehyde NPK compound fertilizers according to market needs. In the early stage, due t...

AI Technical Summary

Problems solved by technology

However, when urea and formaldehyde aqueous solution are mixed to produce white turbidity, the urea-formaldehyde fertilizer made by adding an acidic curing agent and dehydrating and granulating with a kneader under heating has a slowing and controlling effect, but it cannot meet the needs of crops where nitrogen is most needed. nutrient requirements for the growth stage

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