A safe and economical method for reclamation and return of tailings slag field containing toxic heavy metals

Abstract

The invention discloses a safe and economical method of reclaiming a tillable field from a tailing residue field containing toxic heavy metal. The safe and economical method of reclaiming the tillable field from the tailing residue field containing toxic heavy metal includes the following steps. Firstly, the tailing residue field is flattened, rolled and compacted and water exhausting ditches are built up on the periphery of the field according to the terrain and gradients of the tailing residue field. Secondly, tightly rolled concrete is paved on the flattened and rolled tailing residue field and used as an isolation layer, and heavy metal elements in the tailing residue covered by the isolation layer are prevented from penetrating through the isolation layer so that heavy metal content in the soil is covered. Borrowed soil (clean soil) which is in compliance with national farming field soil environment quality standards is covered on the isolation layer. The thickness of the borrowed soil reaches 40cm after being the borrowed soil is tightly rolled. Thirdly, clean soil which reaches 30cm after being rolled tightly is covered on the borrowed soil. Fourthly, a rotary cultivator is used for cultivating in a rotary mode for 20cm to 25cm deep into the clean soil to form soil of a farming layer. Fifthly, the clean soil is covered and a process of soil-ripening and eutrophication is performed. Sixthly, dry land crops such as wheat and corns are planted. Due to application of the isolation layer, the thickness of the covered soil is reduced and cost in reclaiming the farming field is reduced, cultivation area is effectively increased, practicability and generalization performance of the farming field reclaiming technology are greatly improved and important social benefits, environmental benefits and economic benefits are achieved.

Description

technical field [0001] The invention belongs to the field of reclamation and return of tailing ponds, and in particular relates to a safe and economical method for reclamation and return of tailings slag fields containing toxic heavy metals. Background technique [0002] After the metal ore buried deep in the ground is mined underground or in the open pit, the ore must usually go through beneficiation activities, and the useful metal elements or other non-metal elements in it will be further concentrated and enriched for ore smelting. However, after beneficiation enriches useful elements (such as gold, mercury, lead, zinc, chromium, arsenic, copper, zinc, nickel, etc.), the waste of ore beneficiation—tailings, due to existing economic and technical reasons, the tailings There must be a certain amount of heavy metal elements (such as mercury, lead, cadmium, chromium, arsenic, copper, zinc, etc.). , groundwater dozens to tens of thousands of times) will lead to a significant ...

AI Technical Summary

Problems solved by technology

At present, the reclaimed land from the tailings slag field containing toxic heavy metals at home and abroad is only used for planting trees and grass to green the environment, and there is no safe and economical technology for reclamation and returning to the field.

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