Effect Of Leaching Agent Concentration On The Leaching Rate Of Migmatite Ionic Rare Earth Ore

Select Anyuan migmatite ionic rare earth ore in situ leaching technology as the research object,we study the way to optimize the leaching agent concentration in the leaching process from the exchange reaction of the leaching process,permeate flow rate,mass transfer rates,the effect of leaching and leaching kinetics point of view.It will provide a theoretical reference for the mine to choose the best injection concentration and the optimal injection mode which can reduce leaching agent consumption and improve the recovery rate of the rare earth in production.The ion exchange rate of the rare earth leaching process was studied by using the diffuse and column leaching experiments,the results showed that increasing the concentration of the ore leaching agent could accelerate the exchange reaction.The column leaching experiment mode can take advantage of this play,there is conducive to rapid leaching of rare earths.Therefore,select the column leaching experiments to study the other influence factors,and draw the following conclusions:1、Studied on the seepage velocity,which shows that to improve the leaching agent concentration will slow down its penetration rate.It is not conducive to the conclusion of the mechanical dispersion of solute ions.2、The leaching rate of mass transfer was studied,and it was shown that the increase of the concentration of the leaching agent can increase the gradient of the gradient.The solute diffusion rate is far higher than the rate of mechanical dispersion.Though the high concentration of ore leaching agent slows penetration in the ore body,it can leach the rare earth faster.3、The control experiment of six groups of rare earth leaching effect was carried out.The results show that the injection method of ’from strong to light’ is the best.Extension the leaching time of 15g/L concentration can achieve the requirements that to rapid leaching of rare earth and to reduce the consumption and residual of the ammonium sulfate.4、The leaching kinetics of natural particle size extraction was studied.It is further understood that diffusion velocity is controlling the leaching rate in the process of mine leaching.Results shows when the concentration of the leaching agent is 5g/L,the regularity is not obvious.When the concentration is lOg/L,it belongs to the external diffusion control.When the concentration is 15g/L and 20g/L,the leaching process is divided into two stages.The first stage belongs to external diffusion control,and the second stage is a hybrid control of external diffusion and internal diffusion.The research results was applied to the industrial production of test mine to guide on the selection of leaching process best injection concentration and optimal injection mode.It solved the problem of high consumption and low recovery of rare earth,which proved the practicability of the research conclusion.