Preparation method for sustained-release and controlled release compound fertilizer suitable for field crop

Abstract

The invention relates to a preparation method for a sustained-release and controlled release compound fertilizer suitable for field crops and belongs to a mixed fertilizer which can control the releasing rate of nutrition components. The preparation method is characterized by comprising two critical processes which is melting granulating and revolving drum coating; firstly, built-in sustained-release compound fertilizer particles are prepared by the melting granulating; then the compound fertilizer is prepared by heteroallelic particle variable speed and the revolving drum coating; the compound fertilizer comprises the following raw materials according to the weight percentage: 35-65 of urea, 9-36 of monoammonium phosphate or heavy calcium, 8-40 of potassium chloride or potassium sulphate, 1-38 of pelleting accessory, 3-5 of nanoscale chitosan improved concave-convex soil and 1-2 of nanoscale chitosan coating agent. The invention provides the preparation method for the sustained-release and controlled release compound fertilizer applied in the field crops, which can control the releasing rate of the fertilizer efficiency according to the requirement of different stages of the crop growth on the nutrition and provides the timing and defined amount of nutrition for the growth of the crops and has high fertilizer utilization rate; the coating material is easily degraded and is beneficial to the environment protection.

Description

technical field [0001] The invention relates to a preparation method of a slow-release and controlled-release compound fertilizer suitable for field crops, and belongs to the compound fertilizer capable of controlling the release rate of nutrient components. Background technique [0002] Chemical fertilizers are widely used in large quantities and have become one of the most important means of production in agricultural production, accounting for a large share of agricultural industry costs. The water solubility of chemical fertilizers makes them dissolve, decompose, volatilize, and lose rapidly after they are applied to the soil, resulting in low nutrient utilization, and the incompatibility between the demand for nutrients of crops and the supply of nutrients by chemical fertilizers; not only waste of resources, but also agricultural The increase in cost and the pollution of water, air and soil caused by the lost chemical fertilizers pose a threat to the environment on whi...

AI Technical Summary

Problems solved by technology

[0005] 1. It is impossible to control the release rate of fertilizer effect according to the demand for nutrients in different stages of crop growth, and it is impossible to provide timely and appropriate nutrients for crop growth

[0006] 2. Low utilization rate of fertilizer nutrients

[0007] 3. Failure to effectively solve the problems of fertilizer nutrient loss and environmental pollution

[0008] 4. The high tower granulation process in the prior art has single process adaptability, poor compatibility, complex process and high cost

[0009] 5. The coating material is difficult to degrade and pollutes the environment

[0010] 6. The price is high, not suitable for field crops

Images