The invention discloses a circulating bubble leaching method for efficiently removing residual
ammonium salt in a
weathering crust eluviation type
rare earth closed mine field. The circulating bubble leaching method comprises the following steps: preparing a low-concentration composite leaching solution containing a surfactant; pumping the composite leacheate into an
elution column which is connected with a microporous
aeration device and is filled with a
weathering crust
elution type
rare earth sample; and circularly leaching under the condition of bubbles less than 100 microns until the concentration of
ammonium in the obtained leacheate reaches
elution equilibrium, thereby completing the leaching of the residual
ammonium salt. According to the method, the
metal salt and the surface
active agent are used for preparing the composite eluting agent,
calcium ions and the like obtained through synchronous elution from the
tailings are fully utilized, the concentration of the
metal salt in the eluting solution is reduced, and the circulating bubble eluting technology is combined, so that the gas-liquid-
solid three-phase contact area is increased,
desorption of NH4 < + > is accelerated, and efficient elution of residual ammonium salt is promoted; the method has the advantages of low eluant concentration, high elution efficiency and the like, and can provide a new idea for efficient repair of the
rare earth closed mine field.