Mixed sustained-and-controlled-release fertilizer and preparation method thereof

Abstract

The invention relates to a mixed sustained-and-controlled-release fertilizer and a preparation method thereof. The mixed sustained-and-controlled-release fertilizer is prepared from the raw materials, by weight: 20-40% of an organic fertilizer, 20-30% of sustained-and-controlled-release urea, and 30-60% of a common chemical fertilizer. The organic fertilizer is a granular organic fertilizer with organic matter content higher than 15%. The sustained-and-controlled-release urea is sulfur-coated urea. The common chemical fertilizer is a mixture of 2 or more than 2 selected from granular diammonium phosphate, monoammonium phosphate, potassium chloride, and potassium sulfate. According to the invention, the organic fertilizer, the sustained-and-controlled-release urea, and the common chemical fertilizer are well mixed according to the ratio, such that the fertilizer provided by the invention is adopted. Because a certain amount of the organic fertilizer is doped into the common blended fertilizer, soil hardening degradation is prevented, soil is fertile, and cost is reduced. According to the invention, the sulfur-coated urea is used for completely substituting large-particle urea in the blended fertilizer, such that nutrient loss caused by excessive releasing speed of common urea is prevented, and chemical fertilizer dosage is reduced.

Description

technical field [0001] The invention relates to an agricultural fertilizer, in particular to a mixed slow-release and controlled-release fertilizer and a preparation method thereof. Background technique [0002] my country is a large agricultural country, and agricultural development is the guarantee of national economic and social development. Chemical fertilizers play a huge role in agricultural development, such as increasing crop yields, improving soil fertility, and compensating for lack of cultivated land. However, the utilization rate of chemical fertilizers is very low. The utilization rate of nitrogen fertilizer is 25%-40%, phosphorus fertilizer is only about 20%, and potassium fertilizer can reach more than 30%. Moreover, the lost chemical fertilizer will cause environmental pollution. Scientific fertilization, convenient fertilization, and improving the utilization rate of fertilizers have become the issues that farmers are very concerned about today. At presen...

AI Technical Summary

Problems solved by technology

There are some slow-release and controlled-release fertilizers on the market, but there are some problems such as: high cost, rapid release of ordinary urea and nutrient loss, unbalanced nutrition, and complicated fertilization process