Research And Development Of Ecotype Phosphatic Fertilizer

Phosphate ores is not a sort of reproducible resource and will be dried up along with exploitation. The reserves of phosphate ores is abundant in China, but most of them are low-grade. Phosphatic fertilizer production will depend on the low-grade phosphate ores more and more .Because of this, it is urgently important to engage in science research and technology development in order to utilize the low-grade phosphate ores for phosphatic fertilizer production. The conventional means of low-grade phosphate ores is mill run or to triturate the low-grade phosphate ore as phosphatic fertilizer, but both of them are not feasible in fact. If a more feasible technique to product phosphatic fertilizer is developed, that not only the problem to utilize the low-grade phosphate ores will be settled but also the production of phosphatic fertilizer in the neighborhood will be more easily. It is validated that humic acid can improve the effect of phosphatic fertilizer. The higher rate of coversion and the better physical appearance ecotype phosphatic fertilizer is developed, based on low-grade phosphate ore, weathered coal and sulfuric acid as primary material, the mechanics that why the humic acid can improve the effect of phosphatic fertilizer is researched.(1)The chemical property of humic acid is analyzed.(2) The adsorption characters of humic acid to Ca²⁺,Fe³⁺,Al³⁺,H₂PO₄^- are researched. The adsorption isotherms are drawed and the equations are imitated. The infections of consistencies of humic acid are analysed.(3)The structure of weathered coal is analyzed by chemical analysis and infrared spectrum scanner.(4)The adsorbing characters of weathered coal to Ca²⁺,Fe³⁺,Al³⁺,H₂PO₄^- are researched.The equations are imitated and the results accord with the Langmuir equation, the relativity is notable .The sort order of weathered coal's maximum adsorbance to these ions is Fe³⁺>Ca²⁺>Al³⁺>H₂PO₄(5) The technic of extracting humic acid from weathered coal is researched and the results indicate: the temperature is more important for extractioin percentage; the extractioin percentage of activation technics is higher than that of sodium hydroxide technics; the best technics is found.(6)The conventional technics of superphosphate are researched and the best technics are: the dosage of sulfuric acid is 105%, reaction time is 15 minutes, the stir speed is 500 turns per minute, the quality pecent of sulfuric acid is 60%.(7)The technics to produce phosphatic fertilizer by weathered coal and low-grade phosphate ore are studied. The results show:1) The physical characters are improved, the curing time is shorter than before.2) The better pecent of weathered coal is 8%～12%.3) The best technics are: the dosage of sulfuric acid is 105%, reaction time is 15 minutes, the stir speed is 500 turns per minute. the quality pecent of sulfuric acid is 60%.(8)The technics to produce phosphatic fertilizer by humic acid and low-grade phosphate ore are semblable as that by weathered coal and low-grade phosphate ore.(9)The reasons why humic acid can improve efficiency of phosphatic fertilizer are discussed, the results show that the reasons are interrelated to the better adsorbing characters of humic acid.