Study On The Manufacture Of Coated Fertilizer And Controlled Release Effect Of Fertilizer Nutrient

Inorganic mineral and organic-inorganic mixed liquid which are cheap and can be easily found as coated material, simple and practical producing process adopted to manufacture environment-friendly coated controlling release fertilizer are researched successfully. The nutrient controlled release effect of different coated substances was assessed by water culture, leaching, volatilization and pot experiments. It provides the basic information for manufacturing and using the coated fertilizer reasonably, for the approach of reducing nutrient loss, for improving fertilizer using efficiency and reducing ecological environment pollution by theoretical and practical incorporation. The results are as followed:1. The earth column leaching experiment shows that the controlled release effect using the inorganic mineral X(the main component is SiO2 and MgO) as the coated substance is better than the inorganic mineral Y(the main component is SiO2 and Al2O3). It also determines the concentration of agglomerant A (5.0%), B (0.5%) and C (1.6%) which fit for the inorganic mineral. The controlled release effect of AcX is the best.2. The suitable concentration of modified high molecular polymer is the concentration of code 3 by the result of organic-inorganic mixed liquid experiment. The inorganic mineral combined with modified high molecular polymer can increase the permeability of coated fertilizer. Inorganic mineral g compared with inorganic mineral f is more appropriate to be inorganic filling mineral. The proper dosage of inorganic mineral g is g2, considering the permeability of coated fertilizer, producing cost and stability.3. Water culture and water-tolerant rate experiments show initial release of NH4+N of PG, PGgm PGf coated fertilizer decreases by 67.8-86.1% compared with uncoated fertilizer CK. Leaching experiment indicate theleaching peak time of PG, PGg, PGf coated fertilizer is late 38, 36, 35days respectively compared with uncoated fertilizer CK. The volatilization experiments manifest the restrain to nitrogen volatilization of coated fertilizer is apparent. Compared with uncoated fertilizer CK, the nitrogen volatilization of PG, PGg, PGf coated fertilizer decrease by 18.1%, 26.0%, 19.3% respectively.4. The dry rice pot experiment shows that the coated fertilizer of PG, PGg and PGf can improve the nitrogen use efficiency respectively 1.5%, 7.5% and 4.7% compared with the common compound fertilizer. The crop has the biggest biomass production treated with PGg coated fertilizer. In conclusion, The effect of PGg coated fertilizer is the best, considering from diminishing the cost of coated fertilizer, improving fertilizer efficiency, reducing ecological environment pollution.