Self-curing film-coated controlled release fertilizer and preparation method thereof

Abstract

The invention relates to a self-curing film-coated controlled release fertilizer and a preparation method thereof. The preparation method comprises the following steps: adding granulated fertilizer into a pan granulator; spraying glue solution under the condition that the pan granulator rotates so that the glue solution is uniformly distributed on the surface of the granulated fertilizer; spraying calcium-containing powder for curing reaction on the surface of the granulated fertilizer, and continuously rotating until the granulated fertilizer is uniformly coated; and drying and sieving the coated granulated fertilizer. The self-curing film-coated controlled release fertilizer prepared by the invention has the advantages that: a controlled-release layer can be cured in the air, thus the consumption of adhesive and the cost are reduced; the controlled-release layer can slowly form substances capable of being dissolved into water in water through a chemical reaction, and finally, the calcium element in soil can be replenished; the self-curing film-coated controlled release fertilizer is free of environment pollution, completely environment friendly and free of residue of harmful substances; acid soil can be adjusted, and the increasing acidification problem of the soil can be solved; and not only can the yield of crops be increased, but also the quality of the crops can be improved.

Description

technical field [0001] The invention relates to a slow and controlled release fertilizer and a preparation method thereof, in particular to a self-curing coated slow and controlled release fertilizer and a preparation method thereof. Background technique [0002] Urea-based nitrogen fertilizer has a fast nitrification and ammonification speed. In the current crop planting, it often causes excess nitrogen fertilizer in the early stage, resulting in excessive growth, and defertilization in the later stage. At present, the nitrogen utilization rate of my country is only 30%. The development of slow and controlled release fertilizers is imminent. As an environmentally friendly high-tech product, slow-release fertilizer has the advantages of increasing the utilization rate of chemical fertilizers, reducing the amount of chemical fertilizers used and the frequency of fertilization, saving labor, reducing environmental pollution, and improving the quality of agricultural products. ...

AI Technical Summary

Problems solved by technology

[0004] (1) Stable nitrogen fertilizers containing nitrification inhibitors: hydroquinone and dihydroammonia are usually used to inhibit urine enzymes and nitrification agents, and their main functions are to inhibit nitrogen loss during urea conversion and nitrification processes, and reduce leaching and denitrification processes The gaseous loss caused by nitration has a certain effect on prolonging the fertilizer effect. This kind of fertilizer has a long history of development, but it has not yet formed a leading product. The new high-efficiency nitrification inhibitor is expensive, and long-term use has adverse effects on the rhizosphere micro-ecosystem ;

[0005] (2) Organic synthesis of slightly soluble slow-release nitrogen fertilizer: This is a slow-acting and long-acting fertilizer studied in the early stage, including aldolide, oxamide, isobutylidene and other common organic nitrogen fertilizers. Slow nutrient release can effectively improve the utilization rate of fertilizers, but the nutrient release rate is affected by various factors such as soil moisture, PH, microorganisms, etc., and the possibility of artificial regulation is small. The commodity price is also high, and the market development speed is slow. ;

[0006] (3) Polymer-coated slow-release fertilizer: This fertilizer has entered large-scale production, and the controlled-release effect is better. The nutrient release of the fertilizer is mainly affected by temperature, and other factors are less affected. It can realize the growth period of crops. Internal one-time fertilization meets the nutritional needs of crops, significantly reduces the amount of labor, and improves production efficiency. However, the equipment and process of this product are relatively high and the production cost is high, so the market is difficult to accept. On the other hand, this product uses polymer as the coating material. , and polymers generally take 30 to 50 years to degrade in the soil, so this process also has the problem of secondary pollution to the soil; in the era of advocating environmental protection, ordinary resin coatings will face more and more resistance and criticism

However, for crops that avoid sulfur, there is obviously no market for this urea

Moreover, in terms of timeliness, compared with other types of slow-release urea, sulfur-coated urea is slightly short-lived.

Long-term application of sulfur-coated fertilizers leads to acidification of soil

Other inorganic packaged slow and controlled release fertilizers, urea coated with phosphorus and compound fertilizers, have the characteristics of fertilizer wrapped in fertilizer, but after being applied to the soil, they are affected by factors such as water, especially microorganisms, and cannot meet the standards of slow and controlled fertilizers , although the above-mentioned fertilizers can all play the role of fertilizers, increasing the application of chemical fertilizers, the yield has been improved, but in addition to the joy of high yield, the problem of environmental pollution is worrying, the volatilization and leaching of effective nutrients in the soil reduce the utilization of fertilizers rate, not only caused a serious waste of resources, but also caused some pollution to the soil and water ecological environment