In-situ leaching and liquid collecting method for weathered crust leaching-deposited rare-earth ore

Abstract

The invention relates to an in-situ leaching and liquid collecting method for weathered crust leaching-deposited rare-earth ore. The method comprises the following steps: (1) distributing liquid injection holes, which reach a semi-weathered layer, on the surface of an ore body to form a grid, and inserting a PVC pile into each liquid injection hole so that a leaching agent can reach the semi-weathered layer; (2) drilling liquid collecting guide holes, which are perpendicular to the ore body or are inclined upwards at angle of 2-5 degrees, with a kilometer drill in positions 5-20cm below the interface between the semi-weathered layer and the bedrock of a valley of the ore body, and drilling holes in a circle along the ore body from a lower part of the valley; (3) building a liquid collecting ditch along the ore body from a lower part of the valley so as to lead rare-earth leachate, which flows out of the ore body, into the liquid collecting ditch; and (4) building a liquid collecting pool, which is connected with the lower end of the liquid collecting ditch, at the downstream part of the valley so that the rare-earth leachate flows into the liquid collecting pool via the liquid collecting ditch, pumping the rare-earth leachate in the liquid collecting pool into a hydrometallurgical workshop, and performing treatment and extraction to obtain a rare-earth product. According to the method, rare-earth leachate can be recovered to the maximum extent, the rare-earth recovery ratio is effectively increased, and favorable economic benefits are achieved.

Description

technical field [0001] The invention belongs to the technical field of hydrometallurgy, and in particular relates to an in-situ leaching and liquid collection method of a weathering crust leaching type rare earth ore. Background technique [0002] Weathering crust leaching-type rare earth ores are widely distributed in the six provinces of Jiangxi, Guangdong, Fujian, Guangxi, Hunan and Yunnan in southern my country. It is composed of raw rocks such as granite and volcanic rocks containing rare earths, which are chemically and biologically weathered to form clay minerals such as kaolin. It is divided into humic layers, fully weathered layers, semi-weathered layers and bedrock. Hydroxyl hydrated rare earth ions are adsorbed and enriched on clay minerals to form weathering crust leaching type rare earth ores. In industry, ammonium sulfate or ammonium chloride is usually used as a leaching agent, and the rare earth ions are exchanged in the solution through ion exchange by usin...

AI Technical Summary

Problems solved by technology

The traditional outlet cavity is a hole with a height × width of 1.5m × 1m. Due to manual digging, it is not only labor-intensive and time-consuming, but also there are likely to be dead spots in the ore body that are difficult to leach, which affects the recovery rate of rare earths.

The shortcomings of the outlet chamber are as follows: (1) The depth of the hole is generally difficult to exceed 20m, which is not conducive to the seepage of the leachate inside the larger ore body, affecting the full contact between the leachate and the ore inside the ore body, and prone to ore body ore leaching. Take the dead angle; (2) The distance between the outlet chambers is usually 10-30m, which cannot be densely distributed, resulting in the slow seepage of leachate from the ore body between the outlet chambers, and it is difficult for the ore in some parts to fully contact with the leachate , so that the rare earth leaching rate is low; (3) In order to facilitate manual drilling, the liquid outlet chamber is generally located at the junction of the fully weathered layer and the semi-weathered layer, resulting in more semi-weathered layer ore soils that cannot be leached, affecting the recovery rate of rare earths ; (4) Artificial holes are prone to collapse events, there are potential safety hazards, and the life safety of workers cannot be guaranteed