Compound mixed slow release fertilizer using perlite as carrier

Abstract

The invention relates to a compound mixed slow release fertilizer using perlite as a carrier, which is characterized in that perlite is used as the carrier, 0-5-10% sulfuric acid and a 20-40% nitrogen fertilizer (a urea water solution) are mixed in a quantity-equal manner and then mixed with a 10-30% potassium fertilizer (such as a potassium sulfate water solution) in a quantity-equal manner or a quantity-unequal manner, and the weight ratio of raw materials is as follows: 3 parts of water solution is compounded with 1 part of expanded perlite and 2 parts of phosphorus-containing powdered fertilizer. The preparation method of the compound mixed slow release fertilizer comprises the following steps: mixing the sulfuric acid, the nitrogen fertilizer and the potassium fertilizer water solution; spraying onto perlite granules; spraying the phosphorus-containing powdered fertilizer while spraying the mixed solution in a granulator to form a granular three-element compound mixed slow release fertilizer; and drying to obtain the finished product. Through the high adsorptivity of the perlite, the three main elements necessary for plants can be released slowly, and the fertilizer can be prevented from being quickly washed away by rain water; and meanwhile, the hardening of soil can be improved, the loose permeability and the moisture and fertility preserving capability of soil can be increased, and no three wastes are produced.

Description

technical field [0001] The invention relates to the technical field of fertilizer production, in particular to a compound slow-release fertilizer with perlite as a carrier, which is used for industrial production of agricultural compound fertilizer. Background technique [0002] With the technological progress of my country's chemical fertilizer industry, chemical fertilizers are developing in the direction of compounding, slow release and perfect production. In the 1950s, our country adopted the wet method to produce nitrogen-phosphorus compound fertilizer, adding potassium salt to obtain ternary compound fertilizer. However, due to the addition of a large amount of water in the production process, it needs to be dehydrated during drying, resulting in waste of water and electricity. The addition of urea will reduce HF However, it has not been completely eliminated, and the environmental pollution is still serious. [0003] In the 1980s and 1990...

AI Technical Summary

Problems solved by technology

In the 1950s, our country adopted the wet method to produce nitrogen-phosphorus compound fertilizer, adding potassium salt to obtain ternary compound fertilizer. However, due to the addition of a large amount of water in the production process, it needs to be dehydrated during drying, resulting in waste of water and electricity. The addition of urea will reduce HF emission, but it has not been completely eliminated, and the environmental pollution is still serious

[0003] In the 1980s and 1990s, our country broke through the traditional concept of fertilizer production in factories. First, sulfuric acid and urea were made into solid phosphorus solubilizers, and then they were directly granulated with dry mineral powder in production. However, the slow-release solution has not yet been solved. problem