Study On The Effect Of NaCl On KCl Directly Flotation Process

KCl is of great importance to the industrial and agricultural production,and Salt Lake in Qaidam Basin in Qinghai is one of the main sources of KCl.The continuous expansion of the production scale causes the excessive consumption of high grade potassium ore.What’s more,the abraum salts cause serious influences on the recovery rate and the quality of KCl in the flotation process,leading to the decline in the actual production capacity.Although many scholars have done a lot of researches on it,there still exist some disputes about the influence law of abraum salt NaCl on KCl flotati on and the flotation reasons.In this case,the study of the flotation of NaCl with KCl and the weakening of NaCl influences is beneficial to further clarify the flotation mechanism of the potassium salt of Salt Lake and increase the actual production capacity of potassium salt flotation.This paper examines the influences of Na⁺ and Na Cl on KCl flotation.In mechanism,it studies the reasons for NaCl flotation from the aspects of the hydrolysis of carnallite and the fluid state of flotation system.In technology,it tries to use ultrasonic and other methods to regulate the hydrolysis of carnallite and the flotation process of NaCl/KCl.The main research results are as follows:（1）It examines the influences of Na⁺ and abraum salt NaCl on KCl flotation efficiency.The results show that Na⁺ has little effect on KCl,while NaCl particle reduces the recovery rate of KCl.（2）It examines the growth status of the crystal after the hydrolysis of carnallite using scanning electron microscope（SEM）and energy dispersive spectroscopy（EDS）,which is taken as material in the flotation.The results show that KCl and NaCl crystals adhere to each other during the precipitation process,making the selectivity of octadecylamine hydrochloride to KCl worse,further leading to the decrease of NaCl flotation and KCl recovery rate.In addition,the results show that the fluid status has great influences on the flotation process.Therefore,this paper examines the method to regulate KCl and NaCl flotation recovery rate by changing ventilation volume and its effects.It is shown that the recovery rate of KCl and NaCl increases with the increase of ventilation volume under the condition that the ventilation volume is small.When the ventilation volume increases to 40ml/min,the recovery rate of NaCl continues to increase while the recovery rate of KCl is basically stable.Therefore,when the ventilation volume is 40ml/min,NaCl has minimal effect.（3）The use of ultrasonic method to regulate hydrolysis of carnallite proves that the ultrasonic could reduce the adhesion of KCl and NaCl particles.Therefore,it reduces the flotation of NaCl particles and weakens the influence of NaCl particles on KCl flotation.In addition,the results show that the ultrasonic could make the surface of KCl particles rough and enhance the adhesion between the bubbles and particles,thus improving the floatability of KCl particles and increasing its recovery rate from 7.55% to 46.66%.The ultrasonic could also promote the dispersion of ODA in the KCl saturated solution and enhance the interaction of ODA and KCl,thus increasing its flotation recovery rate from 20.84% to 94.24%.（4）In view of the obvious influence of the fluid state on the flotation effect,this paper tries to discuss the influence law of fluid state from the aspect of dynamics.The results show that the flotation of KCl fit well with second-order kinetics model with the kinetics model formula being ε=t/（1.05t+1.25）.The flotation of NaCl fit well with three-parameter fast and slow floating constant model,with the kinetics model formula being ε=0.9954e^-0.00015t+0.0046e^-1.4085.Theoretical analysis of dynamics shows that reducing the mass fraction of the fast floating particles can reduce the flotation of NaCl.In practice,the ventilation volume should be reduced to reduce the number of particles that the fluid takes away.This study can provide theoretical support for weakening the influence of the abraum salt NaCl on the flotation of KCl in practice.