The Preparation Of New Coated Slow-release Fertilizer And Properties Study

Three kinds of environmental friendly coated slow-release fertilizers were prepared whose materials were non-water soluble, and their performances were assessed by crop bilological methods and laboratory methods. Using slow-release coated fertilizer leaching experiments data in different media, predicted equations were established among several evaluation methods, which can supply services to establish the related detection methods in the controlled release fertilizer industry. The major findings of this paper are as follows:1. Three kinds of coated slow-release fertilizers which were A, B, and C were prepared with micro-emulsification and high speed cut techniques. Through its SEM and infrared analysis experiments showed that the coated effect of three kinds of slow-release fertilizers were better, with certain slow-release properties, but the surfaces of the three slow-release fertilizers still exist ammonium nitrate and urea which can precisely meet plants during their growth.2. The three kinds of slow-release fertilizer in the water-soluble experiment, nitrogen accumulation dissolution rate of size was:slow-release fertilizer C>slow-release fertilizer B >slow-release fertilizer A.Compared to pure urea and ammonium nitrate treatment, the difference of dissolved ratio of nitrogen in the same sand column was very obvious. The three kinds of coated slow-release effect of slow-release fertilizers were A> B> C; In the same size soil column, the three kinds of slow-release nitrogen fertilizers release curves and the sand column dissolution curves are similar, and the difference was only dissolved time. The result of three kinds of evaluation methods was consistent.3. The prediction equations were established among the three kinds of evaluation methods of slow-release fertilizers. By one equation and the nitrogen leaching condition of one evaluation, the slow-release fertilizers nitrogen leaching conditions in the other two evaluation methods were more accurately predicted.4. Compared with the same amount nutrients of N quick fertilizer, slow release fertilizers A, B, C increased crop yields, reduced nitrate leaching losses and improved the N,P,K content of brassica chinensis and wheat and increased the protein content of wheat.5. Through single factor experiments, the best process conditions of slow release fertilizers preparation in the lab were determined:the oil phase and emulsifier accounting for 4% of the total, the ratio of ammonium nitrate and urea was 5:5, aqueous accounting for 6% of total weight, temperature is 95℃.