Method for restoring ionic rare earth ore ammonium salt leaching site

Abstract

The invention relates to a method for restoring an ionic rare earth ore ammonium salt leaching site, which comprises the steps of carrying out primary leaching by using a calcium and / or magnesium-containing salt solution and carrying out secondary leaching by using a calcium-containing alkaline aqueous solution or slurry, so that reinforced leaching of residual ammonium salt in the ammonium salt ore leaching site, controllable adjustment of the pH value, in-situ chemical curing of sulfate radicals and rapid regulation and control of the content of calcium and magnesium nutrient elements can be achieved, the used leaching water amount is small, the leaching period is short, the leaching effect is good, the technology is simple, the cost is low, and a solid technical guarantee can be provided for ion type rare earth ore ammonium salt leaching site restoration and eco-friendliness.

Description

technical field

[0001] The invention relates to the technical field of resources and the environment, in particular to a repair method for an ionic rare earth ore ammonium salt leaching site. Background technique

[0002] In ionic rare earth ores, rare earths are adsorbed on aluminosilicate minerals in a hydrated ion state, and the raw ore grade is only 0.03% to 0.1% (REO). my country has pioneered the production of rare earth concentrates by ammonium sulfate leaching-ammonium bicarbonate precipitation enrichment The unique technology has realized the large-scale development and utilization of ultra-low-grade rare earth ores. However, the process is lengthy and the total rare earth yield is less than 70%. The production of 1 ton of rare earth concentrate (REO) consumes 7 to 14 tons of ammonium sulfate and 5 to 8 tons of ammonium bicarbonate, and a large amount of ammonium salt remains in the leaching site and is slowly released, resulting in The ammonia nitrogen in the surfa...

Examples

Embodiment 1

[0055] After leaching with a certain ammonium salt, the pH value of the rare earth tailings is 3.39, the alkaline hydrolysis nitrogen is 1540mg / kg, the available calcium is 32.89mg / kg, the available magnesium is 17.98mg / kg, and the calcium-magnesium ratio is 1.83.

[0056] Use a salt solution containing calcium and / or magnesium to wash the rare earth tailings after ammonium salt leaching once. The concentration of cations in the salt solution containing calcium and / or magnesium is 0.05mol / L, and the salt containing calcium and / or magnesium The liquid-solid ratio of rare earth tailings after leaching solution and ammonium salt is 0.3m 3 / t; Calcium hydroxide solution is used for secondary leaching, and the liquid-solid ratio of the rare earth tailings after the first leaching is 0.4m 3 / t, the molar concentration of calcium hydroxide is 0.02mol / L, and the pH value is 12.53. The leachate obtained from the two washings is returned to the next ionic rare earth mine for leaching. ...

Embodiment 2

[0060] After leaching with a certain ammonium salt, the pH value of the rare earth tailings is 3.39, the alkaline hydrolysis nitrogen is 1540mg / kg, the available calcium is 32.89mg / kg, the available magnesium is 17.98mg / kg, and the calcium-magnesium ratio is 1.83.

[0061] A salt solution containing calcium and / or magnesium is used to wash the rare earth tailings after ammonium salt leaching. The change of cation concentration in the salt solution containing calcium and / or magnesium is shown in Table 2. Salt solution containing calcium and / or magnesium The liquid-solid ratio of rare earth tailings after leaching with ammonium salt is 0.4m 3 / t; Calcium hydroxide solution is used for secondary leaching, and the liquid-solid ratio of the rare earth tailings after the first leaching is 0.4m 3 / t, the molar concentration of calcium hydroxide is 0.02mol / L, and the pH value is 12.53. The leachate obtained from the two washings is returned to the next ionic rare earth mine for leach...

Embodiment 3

[0065] After leaching with a certain ammonium salt, the pH value of the rare earth tailings is 3.39, the alkaline hydrolysis nitrogen is 1540mg / kg, the available calcium is 32.89mg / kg, the available magnesium is 17.98mg / kg, and the calcium-magnesium ratio is 1.83.

[0066] Use a salt solution containing calcium and / or magnesium to wash the rare earth tailings after ammonium salt leaching once. The concentration of cations in the salt solution containing calcium and / or magnesium is 0.05mol / L, and the salt containing calcium and / or magnesium The change of the liquid-solid ratio of the rare earth tailings after the solution and ammonium salt leaching is shown in Table 3; the calcium hydroxide solution is used for secondary leaching, and the liquid-solid ratio of the rare earth tailings after the first leaching is 0.4m 3 / t, the molar concentration of calcium hydroxide is 0.02mol / L, and the pH value is 12.53. The leachate obtained from the two washings is returned to the next ionic ...

technical field

[0001] The invention relates to the technical field of resources and the environment, in particular to a repair method for an ionic rare earth ore ammonium salt leaching site. Background technique

[0002] In ionic rare earth ores, rare earths are adsorbed on aluminosilicate minerals in a hydrated ion state, and the raw ore grade is only 0.03% to 0.1% (REO). my country has pioneered the production of rare earth concentrates by ammonium sulfate leaching-ammonium bicarbonate precipitation enrichment The unique technology has realized the large-scale development and utilization of ultra-low-grade rare earth ores. However, the process is lengthy and the total rare earth yield is less than 70%. The production of 1 ton of rare earth concentrate (REO) consumes 7 to 14 tons of ammonium sulfate and 5 to 8 tons of ammonium bicarbonate, and a large amount of ammonium salt remains in the leaching site and is slowly released, resulting in The ammonia nitrogen in the surfa...

Examples

Embodiment 1

[0055] After leaching with a certain ammonium salt, the pH value of the rare earth tailings is 3.39, the alkaline hydrolysis nitrogen is 1540mg / kg, the available calcium is 32.89mg / kg, the available magnesium is 17.98mg / kg, and the calcium-magnesium ratio is 1.83.

[0056] Use a salt solution containing calcium and / or magnesium to wash the rare earth tailings after ammonium salt leaching once. The concentration of cations in the salt solution containing calcium and / or magnesium is 0.05mol / L, and the salt containing calcium and / or magnesium The liquid-solid ratio of rare earth tailings after leaching solution and ammonium salt is 0.3m 3 / t; Calcium hydroxide solution is used for secondary leaching, and the liquid-solid ratio of the rare earth tailings after the first leaching is 0.4m 3 / t, the molar concentration of calcium hydroxide is 0.02mol / L, and the pH value is 12.53. The leachate obtained from the two washings is returned to the next ionic rare earth mine for leaching. ...

Embodiment 2

[0060] After leaching with a certain ammonium salt, the pH value of the rare earth tailings is 3.39, the alkaline hydrolysis nitrogen is 1540mg / kg, the available calcium is 32.89mg / kg, the available magnesium is 17.98mg / kg, and the calcium-magnesium ratio is 1.83.

[0061] A salt solution containing calcium and / or magnesium is used to wash the rare earth tailings after ammonium salt leaching. The change of cation concentration in the salt solution containing calcium and / or magnesium is shown in Table 2. Salt solution containing calcium and / or magnesium The liquid-solid ratio of rare earth tailings after leaching with ammonium salt is 0.4m 3 / t; Calcium hydroxide solution is used for secondary leaching, and the liquid-solid ratio of the rare earth tailings after the first leaching is 0.4m 3 / t, the molar concentration of calcium hydroxide is 0.02mol / L, and the pH value is 12.53. The leachate obtained from the two washings is returned to the next ionic rare earth mine for leach...

Embodiment 3

[0065] After leaching with a certain ammonium salt, the pH value of the rare earth tailings is 3.39, the alkaline hydrolysis nitrogen is 1540mg / kg, the available calcium is 32.89mg / kg, the available magnesium is 17.98mg / kg, and the calcium-magnesium ratio is 1.83.

[0066] Use a salt solution containing calcium and / or magnesium to wash the rare earth tailings after ammonium salt leaching once. The concentration of cations in the salt solution containing calcium and / or magnesium is 0.05mol / L, and the salt containing calcium and / or magnesium The change of the liquid-solid ratio of the rare earth tailings after the solution and ammonium salt leaching is shown in Table 3; the calcium hydroxide solution is used for secondary leaching, and the liquid-solid ratio of the rare earth tailings after the first leaching is 0.4m 3 / t, the molar concentration of calcium hydroxide is 0.02mol / L, and the pH value is 12.53. The leachate obtained from the two washings is returned to the next ionic ...

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