1 results about "Dried banana" patented technology

This invention relates to a nitrogen and phosphorus biochar-based slow-release fertilizer, its preparation method, and its application. The preparation method includes the following steps: S1. Obtaining a biochar source; the biochar source is dried banana peel powder; S2. Pyrolyzing the biochar source obtained in S1 at 450-550℃ under a protective atmosphere to form potassium-rich biochar; S3. Heat-treating the biochar obtained in S2 at 300-400℃ for 40-90 min under a continuously purging reaction atmosphere, wherein the reaction atmosphere includes: a nitrogen mixture containing 5-20% ammonia and phosphorus-containing precursor vapor; then raising the temperature to 550-650℃ under the same atmosphere and holding it at that temperature for 40-90 min; S4. Stopping the purging of phosphorus-containing precursor vapor, heat-treating the biochar at 500-600℃ for 60-120 min under a continuously purging nitrogen mixture containing 25-40% ammonia, then raising the temperature to 700-750℃ and holding it for 10-15 min; cooling under a nitrogen atmosphere; S5. The oxidation process is carried out in air at 150-250℃. The resulting nitrogen and phosphorus biochar-based slow-release fertilizer can achieve slow nutrient release and is resistant to water washout.