阅读说明：本技术 一种风化壳淋积型稀土矿的浸取方法 (Leaching method of weathering crust leaching type rare earth ore ) 是由 张春雷 袁宪强 付玉华 杨国春 何文 王观石 于 2020-07-08 设计创作，主要内容包括：本发明属于稀土矿湿法冶金技术领域,具体涉及一种风化壳淋积型稀土矿的浸取方法。该方法包括如下步骤：S1：在矿体表面钻孔,通入气体；S2：加注浸取剂,保持一段时间,然后加注顶水。该方法先在矿体中通入气体,能够使得矿体本身发生一定程度的松散,使得矿体内部的微孔隙进一步发展为中、大孔隙,然后注入浸取剂进行浸取,能够提高浸取剂与矿体的接触面积,提高浸取效率和浸出率。本发明先通气体再加注浸取剂的浸取的方法,相比与直接加注浸取剂来说,重大孔隙的存在能够缓和矿体由于吸水发生膨胀带来的影响,能够缓冲稀土矿由于吸水膨胀而引发的山体滑坡。(The invention belongs to the technical field of rare earth ore hydrometallurgy, and particularly relates to a method for leaching weathering crust elution-deposited rare earth ore. The method comprises the following steps: s1: drilling holes on the surface of an ore body, and introducing gas; s2: adding leaching agent, holding for a period of time, and adding top water. The method comprises the steps of firstly introducing gas into an ore body, loosening the ore body to a certain degree, further developing micropores in the ore body into medium and large pores, and then injecting a leaching agent for leaching, so that the contact area between the leaching agent and the ore body can be increased, and the leaching efficiency and the leaching rate are increased. Compared with the method for directly adding the leaching agent, the method for leaching by firstly introducing the gas and then adding the leaching agent can alleviate the influence of the expansion of the ore body due to water absorption and buffer the landslide of the rare earth ore caused by the water absorption expansion.)

1. The method for leaching the weathering crust elution-deposited rare earth ore is characterized by comprising the following steps of:

s1: drilling holes on the surface of an ore body, and introducing gas;

s2: adding leaching agent, holding for a period of time, and adding top water.

2. The leaching method for rare earth ores deposited on weathered crust according to claim 1, wherein the pressure of the gas introduced in the step S1 is 105-110 MPa.

3. The method of claim 1, wherein the gas in step S1 is any one of air, nitrogen or carbon dioxide.

4. The method for leaching rare earth ore from weathering crust elution type according to claim 1, wherein the time for introducing gas in step S1 is 5-15 min.

5. The leaching process for rare earth ores of the weathering crust elution type according to any of the claims 1 to 4, wherein the leaching agent is a sodium salt leaching agent and/or an ammonium salt leaching agent containing a soluble calcium salt in a mass concentration of 1 to 3%.

6. The method of leaching rare earth ores of the encroachment type from weathering crust of claim 5, wherein the soluble calcium salt is calcium chloride or calcium oxalate;

preferably, the soluble calcium salt is calcium oxalate.

7. The method of claim 5, wherein the leaching agent has a pH of 5 to 7.

8. The leaching process according to any one of claims 1 to 7, wherein the sodium salt and/or ammonium salt concentration in the leaching agent is 1 to 3% by mass.

9. The method of leaching rare earth ore of claim 8, wherein the top water contains sodium alginate;

preferably, the mass concentration of the sodium alginate is 3-8%.

10. The leaching process for rare earth ores of the weathering crust elution type according to anyone of the claims 1 to 9, wherein the step S2 is maintained for 80 to 120 min.

Technical Field

The invention belongs to the technical field of rare earth ore hydrometallurgy, and particularly relates to a method for leaching weathering crust elution-deposited rare earth ore.

Background

The weathering crust eluviation type rare earth ore (also called ion adsorption type rare earth ore) is a rare earth ore which is special in China and widely distributed in Jiangxi, Fujian, Guangdong, Hunan, Guangxi and other areas in the south of China, the rare earth ingredient of the rare earth ore is rich in medium and heavy rare earth elements, is a main source of medium and heavy rare earth in China, and has great commercial value. The weathering crust elution type rare earth mineral is clay mineral, mainly composed of kaolinite, halloysite, montmorillonite and the like, the clay mineral is a rare earth load phase, wherein about 85% of rare earth is adsorbed on the clay mineral by hydrated or hydroxyl hydrated ions, and an ion exchange resin with uneven size and complex structure is formed. Therefore, the conventional physical ore dressing method cannot enrich the rare earth, and the chemical leaching technology is generally adopted to recover the rare earth from the rare earth ore.

Weathered leaching type rare earth ores are generally subjected to in-situ leaching for rare earth recovery. The in-situ leaching process is a new mining method, in which leaching agent solution is uninterruptedly injected into the ore body of the stope from a liquid injection shallow well, so that the cations in the electrolyte exchange with the rare earth ions in the ore, and the rare earth ions enter the leaching solution to produce a mother liquor for leaching rare earth, the mother liquor seeps from one side of a liquid collecting ditch and then is collected in a liquid collecting pool, and the mother liquor in the collecting pool is purified and then is precipitated by oxalic acid or ammonium carbonate to recover rare earth. In-situ leaching mining has been widely applied because of the advantages of no damage to the terrain and the landform, no peeling of vegetation and surface soil, no tailing discharge, reduced labor intensity, little influence on the environment, capability of mining ores which cannot be mined by the conventional mining method, full utilization of resources, capital investment saving, production cost reduction, obvious social benefit and the like.

However, in the in-situ leaching process, landslide is caused by improper liquid injection, the main reason is that clay minerals in the weathering crust leaching type rare earth ore absorb water to swell, and when the component force of downward sliding of the gravity of the mountain is greater than the sum of the structural force of the ore and the frictional resistance of the sliding of the ore, the landslide is easy to occur, so that not only is the farmland damaged and the environment polluted, but also the rare earth leaching amount and the leaching agent are lost, and the economic index of the in-situ leaching technology is reduced.

Disclosure of Invention

Therefore, the invention aims to overcome the defects that an ore body is easy to absorb water and expand, landslide is easy to occur and the like in the rare earth ore in-situ leaching process in the prior art, and provides the leaching method of the weathering crust elution-type rare earth ore.

Therefore, the invention provides the following technical scheme:

a weathering crust leaching type rare earth ore leaching method comprises the following steps:

s1: drilling holes on the surface of an ore body, and introducing gas;

s2: adding leaching agent, holding for a period of time, and adding top water.

Further, the pressure of the gas introduced in the step S1 is 105-110 MPa.

Further, the gas in step S1 is any one of air, nitrogen gas or carbon dioxide gas.

Further, the time for introducing the gas in the step S1 is 5-15 min.

Further, the leaching agent is a sodium salt leaching agent and/or an ammonium salt leaching agent, and the leaching agent contains soluble calcium salt with the mass concentration of 1-3%.

Further, the soluble calcium salt is calcium chloride or calcium oxalate;

preferably, the soluble calcium salt is calcium oxalate.

Further, the pH of the leaching agent is 5-7.

Further, the mass concentration of the sodium salt and/or the ammonium salt in the leaching agent is 1-3%.

Further, the top water contains sodium alginate;

preferably, the mass concentration of the sodium alginate is 3-8%.

Further, the step S2 is kept for 80-120 min.

The technical scheme of the invention has the following advantages:

1. the invention provides a weathering crust elution-type rare earth ore leaching method, which comprises the following steps: s1: drilling holes on the surface of an ore body, and introducing gas; s2: adding leaching agent, holding for a period of time, and adding top water. The method comprises the steps of firstly introducing gas into an ore body, loosening the ore body to a certain degree, further developing micropores in the ore body into medium and large pores, and then injecting a leaching agent for leaching, so that the contact area between the leaching agent and the ore body can be increased, and the leaching efficiency and the leaching rate are increased. Compared with the method for directly adding the leaching agent, the method for leaching by firstly introducing the gas and then adding the leaching agent can alleviate the influence of the expansion of the ore body due to water absorption and buffer the landslide of the rare earth ore caused by the water absorption expansion.

2. The weathering crust elution-type rare earth ore leaching method provided by the invention has the advantage that the pressure of gas introduced in the step S1 is 105-110 MPa. The invention can ensure that large and medium pores are formed in the ore body by controlling the gas pressure, and can avoid landslide caused by overlarge pressure.

3. According to the weathering crust elution-type rare earth ore leaching method, the time for introducing gas in the step S1 is 5-15 min. The invention can ensure the formation of large pores in the ore body by controlling the time of introducing the gas, thereby being capable of buffering landslide caused by water absorption expansion of the rare earth ore.

4. The leaching agent is a sodium salt leaching agent and/or an ammonium salt leaching agent, and contains soluble calcium salt with the mass concentration of 1-3%. The top water contains sodium alginate; preferably, the mass concentration of the sodium alginate is 3-8%. The calcium salt can enable sodium alginate to generate certain cross-linking reaction when the top water is injected, so that the adhesive force between ore bodies is increased, a certain fixing effect is realized on the ore bodies, the phenomenon of landslide is avoided, and the expansion rate of the ore bodies is reduced. The soluble calcium salt is preferably calcium oxalate, and the existence of oxalate ions can enable rare earth ions in rare earth ore to be leached out more easily, so that the leaching rate of rare earth is improved.

5. The weathering crust elution-type rare earth ore leaching method provided by the invention is characterized in that the leaching time in the step S2 is kept for 80-120 min. The leaching time is obviously shortened, and the leaching rate of the rare earth is also improved.

Detailed Description

The following examples are provided to further understand the present invention, not to limit the scope of the present invention, but to provide the best mode, not to limit the content and the protection scope of the present invention, and any product similar or similar to the present invention, which is obtained by combining the present invention with other prior art features, falls within the protection scope of the present invention.