Biological biodegradable self-control slow-releasing fertilizer and preparation method thereof

Abstract

The invention discloses a biodegradable self-controlling slow-release fertilizer which is produced by uniformly coating a layer of controlled-release layer of water soluble macromolecule polymer at the surface of the urea or complex fertilizer grain. The weight ratio of the complex fertilizer grain to macromolecule polymer is 0.3-0.4:9.7-9.6. The macromolecule polymer is produced in proportion of fibrin, oxidized starch, polyvinyl alcohol, polyurethane prepolyme, epoxide resin, epoxide resin solidified agent, cross linker, emolsifier, ignition primer, deionized water. The invention adopts glue and latex crosslinking with a biodegradable material to improve the controlled-release capability of the fertilizer and conquer the ''white pollution'', increase the usage ratio of nitrogen of 20-35%, and satisfy the crop need in a whole growth period.

Description

technical field [0001] The invention relates to a self-controlled slow-release fertilizer and a preparation method thereof, in particular to a biodegradable self-control slow-release fertilizer which sprays a layer of water-soluble high polymer material on the surface of urea or compound fertilizer particles as a controlled-release layer and its preparation method. Background technique [0002] Chemical fertilizers are commonly and widely used as conventional fertilizers in crop planting, and they are easy to apply and have outstanding effects. However, there are many problems in the use of chemical fertilizers. One of the most prominent problems is the low nitrogen use efficiency and the resulting The economic loss and environmental pollution caused by the large-scale application of nitrogen fertilizer. How to greatly improve the nitrogen use efficiency of chemical nitrogen fertilizers and give full play to the role of chemical fertilizers is one of the most prominent prob...

AI Technical Summary

Problems solved by technology

[0004] Inorganic coated fertilizers mainly use phosphate rock powder, calcium magnesium phosphate fertilizer, talcum powder, gypsum powder, fly ash, organic or inorganic bonding materials as coating materials in China (see Chinese patents 02126743.x, 03106547.3, 200410024201.1, 200610045310.0 etc.), although these inorganic coated fertilizers are cheap and simple to make, they have poor nutrient controlled release performance and low nitrogen use efficiency, and one-time application will easily cause crops to have defertilization phenomenon in the later stage; foreign countries mainly use TV.A comPany, USA Developed sulfur-coated urea (SCU) (US3295950) as a representative, although its price is not high, but the problem is that ① it is difficult to strictly control the release rate of its nutrients, because the sulfur coating is brittle and will The rupture of the membrane shell will cause all the nutrients in the membrane to be released suddenly, also known as "destructive release", which will often cause damage to the root system of the crop; ②After a large amount of sulfur shells are decomposed by microorganisms in the soil, it is easy to cause soil acidification; ③Sulfur coating Urea also has the problem that the sulfur coating is easy to oxidize and break, which is not conducive to handling

Although this process can evenly spray the membrane material on the surface of fertilizer particles, it has high energy consumption, and it is difficult to fully recover the solvent, which is easy to cause pollution to the production workshop and the surrounding environment, and it is difficult to achieve mass production by using the fluidized bed process; in China , the organic polymer coated fertilizer is represented by the thermosetting epoxy resin coated controlled release fertilizer described in Chinese patent 2004100240497. Compared with the above organic polymer coated fertilizer, this patent solves the complex coating process and the impact of organic solvents on the production workshop and its surroundings. The problem of environmental pollution has the advantages of good nutrient controlled release performance and high nitrogen utilization rate. The disadvantages are that ① the coating material is not biodegradable, and it is easy to cause "white pollution", ② the production cost is high, and ③ the scope of applicable crops is narrow, only It is suitable for horticultural crops, lawns, golf courses and ornamental plants, etc., which is not conducive to the promotion and application of food crops

Images