Effect Of RAW Material Properties Of Blended Fertilizers On Application Of Bulk Blending Fertilizers

Bulk Blending?BB?fertilizer is conteined by two or more granular high nutrient raw materials as needed.Due to its easy formulation adjustment,so the nitrogen,phosphorus and potassium nutrient ratios can be adjusted at any time,based on the soil type,nutrient status,and crop needs.However,there are also several problems in the production,transportation and application of the BB fertilizers.Such as due to the incorporation of basic fertilizers for nitrogen,phosphorus and potassium in fertilizers,there have differences in physicochemical properties such as nutrient content,morphology,particle size and apparent density.Therefore,it will be easy to occur delamination during production,transportation and application,resulting in nutrient separation,which will affect the application effect.At present,there is still a lack of systematic research on the performance and adaptability of BB fertilizers all over the world.For the above problems,this study selects 22 basic raw material fertilizers commonly used in the market as research objects,analyze and evaluate its physical and chemical properties?Including:average particle size,uniformity index,hardness,angle of repose,density,pH,salt index,critical moisture absorption?.According to the main physical indicators?density,average leading particle size,angle of repose?affecting the nutrient distribution of blended fertilizers,the basic raw material fertilizers are blended.Evaluation of chemical properties of blended fertilizers?acidity,salt index and critical moisture absorption?,and use the spiral and external wheel row fertilizer machines for laboratory simulation fertilization tests,in order to evaluate the nutrient distribution during the application of BB fertilizers.The results of this study can provide theoretical basis for the selection of BB fertilizer raw materials.Evaluation of blending effect and adaptability,and use of spiral and external wheel row fertilizer machine for laboratory simulation of fertilization test,to evaluate the nutrient distribution during the application of blend fertilizers.The results of this study can provide theoretical basis for the selection of blended fertilizer raw materials.Test result display,the average dominant particle size?SGN?of nitrogen,phosphorus,and potassium fertilizers in the tested fertilizers were 3.05 mm-4.69 mm,2.64 mm-3.45 mm,and2.81 mm-3.48 mm.The Uniformity Index?UI?was 41.68-69.94,46.03-60.08 and 40.27-47.27.The densities were between 0.71 g/cm³-0.87 g/cm³,0.84 g/cm³-1.05 g/cm³ and 1.03 g/cm³-1.19g/cm³.The overall trends were as follows:potash>phosphate>nitrogen fertilizer.The hardness of nitrogen fertilizer in the tested fertilizers was generally low.Except for ammonium chloride?N₆?produced in Jiangsu,the hardness of other fertilizers was between 0.20 N-13.27 N;the hardness of phosphorus and potassium fertilizers was relatively high,which was 27.47 N-41.38N and 23.55 N-48.47 N.The results of physical and chemical indicators of basic raw material fertilizers showed that 80%of raw material fertilizers meet the blending standards and are suitable for blending.Blended fertilizer pH test results show,ratio of 1:1:1 mixture ratio and nutrient ratio 2:1:1,the difference in acidity and alkalinity is not obvious.Comparative analysis of raw material pH to draw a conclusion,phosphate fertilizer mainly affects the pH after blending.The order of fertilizers affecting the pH and pH of the blended fertilizers should be:monoammonium phosphate>diammonium phosphate>nitrogen fertilizer>potash fertilizer;Bulk blending fertilizer salt index results.The simulated fertilization test results were processed by DPS software data and analyzed and compared.When the advancing speed of the row fertilizer machine was 6 km/h,the blending ratio was 2:1:1,In addition to the salt ratio of 2:1:1 for the F9 blended fertilizer,the salt index was lower than the salt ratio of 1:1:1 for the nutrient ratio,The ratios of nutrients to water ratios of 2:1:1 were higher in the other treatments than in the salt ratio of 1:1:1,Because of its different nitrogen fertilizers other treatments.Comparative analysis of the salt index up to F5 and salt index up to F10 before and after mixing,Potash fertilizer is the main factor affecting the salt index after mixing raw material fertilizers.In this experiment,when the ratio of nutrient solution was 1:1:1,the critical moisture of fertilizer was in the range of 47.0%RH-79.0%RH.Fertilizer critical moisture absorption in the range of 47.0%RH-80.0%RH at a ratio of 2:1:1.The experimental results show that the use of a fertilizer with a high critical hygroscopic temperature is more conducive to the blending and storage of fertilizers.After analysis and comparison,it was found that the advancing speed of the row fertilizer machine was 6 km/h and the blending ratio was 2:1:1.The test results are closest to the theoretical values and have high availability.Among,the most uniform distribution of nutrients after application is F5?N₁P₁K₅,blended according to the principle of SGN similarity?,the most uneven is F9?N₇P₇K₅,blended according to SGN dissimilar principle?.In addition,Raw material fertilizer SGN values are more suitable for blending between 3.40 mm-3.48 mm.The smaller the raw material fertilizer SGN difference,the more uniform the nutrient distribution after application.The shape of K fertilizer and ammonium sulfate are irregular polygons,the angle of repose is larger.The angle of repose to be smaller,the friction force is smaller,the fluidity is better.Use raw material fertilizer with a small angle of repose,and reduce the difference in the angle of repose of raw material fertilizers,it can reduce the separation of fertilizer nutrients.In this examination,the raw material fertilizer density was between 0.71g/cm³-1.19 g/cm³,and there was no significant effect on nutrient uniformity after blending.