RU2339456C2 - Gold ore dressing method - Google Patents

Abstract

FIELD: mining engineering; processes.

SUBSTANCE: method involves roughing, cleaning and recleaner flotation. It provides withdrawal from flotation into the flotation concentrate of the froth of the roughing flotation that was obtained at the initial stage in the course of time of up to 25% of the total time of the roughing flotation. Besides, froth was obtained from the first cleaning flotation in the course of time of up to 50% of the time of the first cleaning flotation.

EFFECT: increased extraction of gold; reduced loss of gold with the flotation tails and enhanced economic efficiency of the gold extraction process owing to reduced consumption of reagents.

2 cl, 1 dwg, 1 tbl

Description

The invention relates to methods for producing precious metals, and more specifically to methods for foam flotation of gold-bearing ores, and can be used in the mining and metallurgical industry for the extraction of gold from primary refractory ores.

Known methods of flotation concentration of precious metal ores, consisting of the main, purification and control flotation with the allocation of gold-containing concentrate in the form of a foam product and tailings in the form of a chamber product. [RF patent No. 2085299. Production line for the processing of mineral raw materials containing precious metals. JSC Irgiredmet. Stated November 16, 1994, publ. July 27, 1997]. The production line includes sequentially connected devices for mixing pulp with flotation reagents installed during the technological process, two flotation machines - one for the primary separation of saturated agglomerates into the foam product, the other for their secondary isolation. A distinctive feature is that the saturated primary sinter agglomerate is combined with the chamber product of control purification and, after contacting with the flocculant, enters the primary flotation.

A disadvantage of the known production line is the dilution of the easily floated saturated agglomerate of primary flotation separation with the chamber product of the purification control operation, which helps to reduce gold recovery and reduce the efficiency of the enrichment process.

The prototype of the invention is a method of enrichment of primary gold-bearing ores [Kuzina Z. P., Antsiferova S. A., Samoilov V. G. The optimal scheme of ore preparation and flotation of refractory gold-bearing ores of the Bogolyubovsky deposit. Non-ferrous metals, 2005, No. 3, p.15-17]. The enrichment process in the known method includes two basic flotation operations, two control and two purifications of the foam product of the main flotation, working in a closed cycle with the foam product of the control operation and the first tailings tailings. As a result of flotation concentration of refractory gold-arsenic ore, sulfide gold-containing concentrate is received, which is fed to hydrometallurgical processing, and tails. The recovery of gold in gold-bearing concentrate is 84.2% with a yield of concentrate of 7.4% and a content of 50.0 g / t in it.

A disadvantage of the known method of beneficiation of primary gold-bearing ores is the insufficiently high extraction of gold into concentrate, as well as the high loss of gold (0.75 g / t) with flotation tailings. In addition, the disadvantage of the prototype is the increased consumption of reagents, helping to reduce the economic efficiency of the process.

The objective of the invention is to increase the extraction of gold, reducing the loss of gold with tailings of flotation, as well as increasing the economic efficiency of the technological process for the extraction of gold by reducing the consumption of reagents.

The problem is solved in that in the method of beneficiation of gold-bearing ores, including the main, purification and control flotation to obtain a gold-containing flotation concentrate from foam products and tailings from a chamber product of control flotation, according to the invention, the foam product of the main flotation obtained at the initial stage over a period of time up to 25% from the total time of the main flotation, as well as the foam product of the first flotation flotation obtained during the time up to 50% of the time of the first flotation flotation, withdrawn from flotation, bedinyayut during flotation concentrate and fed to the metallurgical operation. The foam product obtained during the remaining time of the main flotation is sent to a cleanup flotation. The foam product of the last recycle flotation is combined with a flotation concentrate. The foam control flotation product is returned to the main flotation. The flotation concentrate is sent to thickening, then to metallurgical operations.

The technical result of the invention is achieved by withdrawing from the process gold-bearing sulfides in the form of a foam product having a high flotation rate into a flotation concentrate at the initial stage of flotation, which proceeds over time up to 25% of the total time of the main flotation. The isolated flotation concentrate, in terms of the content of gold and related elements (sulfide sulfur, arsenic, iron) in it, meets the requirements of the gold extraction process and does not need clean flotation, which contributes to the loss of gold from the flotation concentrate. The withdrawal of the foam product at the initial stage from the main flotation process contributes to the solution of the problem of the invention - firstly, to increase the extraction of gold in flotation concentrate by 1.6% with a higher gold content in it compared to the prototype (50 g / t), and secondly , reduction of gold losses from flotation concentrate at the cleanup and main flotations and, thirdly, reduction of reagent consumption.

The technical result is also achieved by the withdrawal of the foam product at the initial stage of the first cleaning operation for up to 50% of the total time of the first cleaning in the finished flotation concentrate. The dedicated flotation concentrate does not need further refinement to improve the quality, which contributes to the accumulation of metal inside the circuit and additional losses with flotation tailings. Thus, the withdrawal of the foam product from the process at the initial stage of cleanup flotation contributes to an increase in gold recovery.

The essence of the proposed method is illustrated by the drawing, which shows the technological diagram of the apparatus and shows the movement of flotation products. The technological scheme contains the following devices: 1 - contact tank, 2 - main flotation flotation machine, 3, 4 - cleanup flotation flotation machines, 5 - control flotation flotation machine, 6 - thickener.

The method is as follows. Ore that has undergone preparatory operations for flotation in one of the known ways, with a grade of 85-89% grade - 0.074 mm, enters the contact tank 1 for processing flotation reagents. From the contact tank, the pulp is fed into the flotation machine 2 for the main flotation. The foam product of the first chamber of the flotation machine 2, obtained within 2.5 minutes, in the form of a flotation concentrate is sent to subsequent metallurgical operations, for example, to a thickener 6 for thickening. The foam product obtained in the remaining chambers of the flotation machine 2 of the main flotation for 9.5 minutes is sent to the flotation machine 3 for the first flotation flotation. The foam product of the first chamber of the flotation machine 3, obtained within 3 minutes from the time of the first flotation flotation, is sent as a flotation concentrate to the thickener 6. The foam product of the remaining chambers of the first flotation flotation from the flotation machine 3, obtained in the remaining time of 3 minutes, is sent to the flotation machine 4 for second flotation flotation. The foam product of the second flotation flotation from flotation machine 4 is sent as a flotation concentrate to thickener 6. The chamber product of the main flotation from flotation machine 2 is sent to flotation machine 5 for control flotation. The foam product of the control flotation is returned to the second chamber of the flotation machine 2 of the main flotation. The chamber product of the first cleaning operation is returned to the second chamber of the main flotation flotation machine 2. The chamber product of the second flotation flotation unit from the flotation machine 4 is returned to the receiving pocket of the first chamber of the flotation machine 3 of the first flotation operation. The chamber product of control flotation from flotation machine 5 is withdrawn in the form of flotation tails with a gold content of ≤0.5 g / t.

Flotation concentrates are combined in a thickener 6 and sent to metallurgical operations, for example, biooxidation and cyanidation, or sent to pyrometallurgical operations. Technological indicators of flotation concentration obtained by the present method are shown in the table.

Table
Primary gold ore dressing Product Name Exit, % Content, Au, g / t Recovery% Flotation concentrate 3.56 93,99 85.8 Flotation tails 96.44 0.57 14.2 Ore 100.00 3.76 100.0

Claims (2)

1. The method of beneficiation of gold-bearing ores, including the main, purification and control flotation to obtain a gold-containing flotation concentrate from foam products and tailings from a chamber product of control flotation, characterized in that the foam product of the main flotation obtained at the initial stage over a period of time up to 25% of the total time of the main flotation, as well as the foam product of the first flotation flotation obtained during the time up to 50% of the time of the first flotation flotation, removed from flotation, combined into a flotation concentrate spending and sent to metallurgical operations. 2. The method according to claim 1, characterized in that the foam product obtained during the remaining time of the main flotation is sent to recycle flotation, the foam product of the last recycle flotation is combined with flotation concentrate and the foam product of the control flotation is returned to the main flotation.