Reserch On Potassium Resources From Tailings Of Phosphate-potassium Ores After Gravity Concentration

Soluble potassium resource is very shortage in our country, and refractory potashmine has not been effectively utilized. These problem lead to the lack of potassium in thefertilizer application, potash fertilizer is mainly dependent on imports. This paper used akind of phosphate-potassium ore tailings as the raw materials ore, which has considerablepotassium content. In order to solve the problem of waste of tailing ore resources, butalso take full advantage of its rich potash resources, while providing the basis for theapplication of poorly soluble potash. This paper studied the process of extractingpotassium from rich potassium tailings with sulfuric acid under normal temperature andpressure. The experiment studied the influence of various factors. Extracting solublepotassium from phosphate, rich potassium tailings and sulfuric acid system was studiedin this paper, single factor experiment and orthogonal experiment is combined to studythe optimum process conditions, also investigate the influence of the addition of someadditives on the experiment, the main research content is as follows:1. It is a process of extracting potassium from rich potassium tailings with sulfuricacid under the normal temperature and pressure, the experiment studied the concentrationof sulfuric acid, the dosage of sulfuric acid and the reaction time on the influence of thereaction. The result of the experiment showed that the optimum conditions for theleaching were the sulfuric acid concentration of60%, the dosage of2.5mL/g, thereaction time of2h, the leaching rate of potassium can reached12%, this indicated thatsulfuric acid can resolve the potassium-rich tailings under the room temperature and thenormal atmospheric pressure, however, leaching rate of the potassium is very low, onlyfurther to improve the process condition can increase the leaching rate of potassium.2. The experiment also studied extracting potassium from the potassium-rich tailingswith sulfuric acid by phosphate as the additive, the result indicate that the leaching rate ofpotassium is obviously increased. The optimum conditions for the leaching process werethe sulfuric acid concentration of60%, the mass ratio of0.8, the dosage of4g/mL,reaction temperature of90℃, the reaction time of2h, under the above condition, the leaching rate of potassium can reached74%. Through the orthogonal experiment canconcluded that the order of the influence of several factors on the experimental sequenceis the mass ratio, sulfuric acid concentration, the dosage of sulfuric acid, the mass ratio,and the sulfuric acid concentration has a large influence on the process of extractingpotassium from the potassium-rich tailings.3. In order to further increase the leaching rate, add the fluoride as additive base onthe potassium-rich tailings, sulfuric acid and phosphate system to study the influence onthe experiment. The addition of calcium fluoride and sodium fluoride has more obviousincrease on the potassium leaching rate, with the added effect of calcium fluoride isbetter than sodium fluoride, potassium leaching rate are increased with the increase ofadding calcium fluoride, the adding dosages in60g/100g ores is the most appropriate,the leaching rate of potassium can be improved on the basis of the original6%to8%.4. To further optimize reaction conditions and improve the potassium leaching rate.The surfactant was used as additive to add in the potassium-rich tailings, sulfuric acidand phosphate system to discuss the influence of different type of surfactant on theexperiment. An increase in the amount of anionic surfactant is significantly improved thepotassium leaching rate, the dosage in30~50g/100g tailings has the best effect; Theaddition of cationic surfactants also has a small increase on the potassium leaching rate,but the effect is not obvious, And the high dosage of potassium will lead the leaching ratedecline; Non-ionic surfactant and amphoteric surfactant has less effect on the experiment.Add anionic surfactants and cationic surfactants in a certain proportion has a good effecton the experiment, the leaching rate of potassium can promote a dozen percentage whenthe mass proportion is3:1.