CN86105982A

CN86105982A - Low-temperature sulfidation roasting—recovery of copper, gold and silver by mineral processing

Info

Publication number: CN86105982A
Application number: CN86105982.4A
Authority: CN
Inventors: 刘纯鹏; 谢宁涛; 何能安
Original assignee: Research Institute Of Dongchuan Mining Bureau; Kunming University of Science and Technology
Current assignee: Research Institute Of Dongchuan Mining Bureau; Kunming University of Science and Technology
Priority date: 1986-09-03
Filing date: 1986-09-03
Publication date: 1988-04-20
Also published as: CN1014802B

Abstract

低温硫化焙烧—选矿法回收铜、金、银是针对低品位难选的结合性氧化铜矿及其伴生贵金属采用低温硫化焙烧—浮选联合工艺，使人工硫化后的铜及其伴生的贵金属从原矿基体脱出获得优良的浮选效果。比之直接选矿或直接湿法浸溶具有成本低、工艺流程简单、设备投资低、能耗少、易实现及无污染等优点。The low-temperature sulfidation roasting-mineralization method to recover copper, gold and silver is to use low-temperature sulfidation roasting-flotation combined process for the low-grade refractory bonded copper oxide ore and its associated precious metals, so that the artificially sulfided copper and its associated precious metals are separated from the The raw ore matrix is released to obtain excellent flotation effect. Compared with direct beneficiation or direct wet leaching, it has the advantages of low cost, simple process flow, low equipment investment, low energy consumption, easy realization and no pollution.

Description

Recovery of copper, gold and silver by low-temp. sulfurizing roasting-ore dressing method

The low-temperature sulfurizing roasting-ore dressing process for recovering copper, gold and silver is one kind of effective method in extracting metallurgy.

Many researches and experiments of various scales are carried out on complex and difficult-to-sort copper oxide ores by many people at home and abroad for over twenty years, and an optimal scheme suitable for treating the ore body cannot be determined up to now. The invention aims to sulfurize the ore at low temperature (about 250 ℃) in a short time to obtain sulfide ore, then directly float the sulfide ore, and concentrate copper, gold and silver by using conventional reagents to discard a large amount of waste rock.

The key point of the technology is to control the technological conditions of low-temperature sulfurizing and roasting to sulfurize copper and its oxide and to produce sulfide preferentially and separate from its matrixThen, the artificial sulfide ore with better flotation performance than copper oxide ore is floated to enrich copper, gold and silver in the concentrate, and the process conditions of the two processes of low-temperature vulcanizing roasting and flotation are described as follows.

First, low temperature sulfurizing roasting

1. Process conditions

Roasting temperature: 250 deg.C

Roasting time: 30 to 40 minutes

Ore particle size: grinding to less than 200 meshes and accounting for 93%

Additive: adding sulfur powder 0.5% (ore: sulfur is 100: 0.5)

2. Roasting equipment

A furnace-like structure as recommended by the description figures can be used. The figure is a schematic view of a sealed horizontal low-temperature vulcanizing rotary kiln, which mainly comprises three parts. The sealed mixing bin 1, the sealed gate valve 2 and the feeding bin 7 form a bin system, and the mixed mineral aggregate is input into the roasting kiln from the bin system. The kiln body system is composed of a heat insulation layer 3, an electric heating wire 4, a cylindrical kiln body 5, a water-cooling sealing ring 6 and a riding wheel 10, mineral materials enter a sealing bin system after low-temperature vulcanization roasting, the sealing bin system is composed of a sealing bin 8 and a sealing gate valve 9, and the roasted mineral materials are discharged from the sealing bin system.

And secondly, flotation. The flotation closed circuit flow and the medicament system are shown in the attached figure 2 of the specification.

The artificial sulfide ore produced from the roasting furnace is sent to flotation. The flotation process comprises the steps of primary roughing, secondary roughing and scavenging, wherein the primary roughing and the secondary roughing are respectively selected, and the middlings are respectively returned to the primary roughing and the secondary roughing.

The method for treating the Tongdianite obtains good technical and economic indexes as follows.

1. Grade of valuable metal of raw ore: copper 0.62%, silver 5 g/ton, gold 0.059%/ton.

2. And (3) low-temperature vulcanization roasting conditions: the temperature is 250 ℃, the roasting time is 30 minutes, the raw ore is dry-ground until 93 percent of the raw ore passes through a 200-mesh sieve, and the adding amount of sulfur is 0.5 percent.

3. The flotation flow and the chemical system are shown in table 1.

4. The obtained technical and economic indexes

Copper concentrate grade: copper 10.2%, silver 78.3 g/ton, gold 1.35 g/ton

And (3) recovery rate: 83% of copper, 72.3% of silver and 91.6% of gold

Yield of concentrate: 4 to 5 percent

Compared with the high-pressure ammonia method, the segregation method and the fire method adopted at present, the method has the following advantages:

1. the roasting equipment is simple at normal pressure and low temperature, the investment is low, the realization and the operation are easy, and special reagents and refractory materials are not needed;

2. the roasting energy consumption is low, for example, the coal consumption (not counting the heat utilization rate) is only 9.1 kg/ton of standard coal by adopting the dry grinding theory;

3. the raw ore grade is low, and the recovery rates and the grades of copper, gold and silver in the concentrate can achieve better effects;

4. the whole process flow only produces a small amount of sulfur dioxide, a part of sulfur in the concentrate can be recovered in converter blowing, and sulfur dioxide produced by roasting can also be recovered, so that no pollution is basically achieved.

Claims

1. A non-ferrous metal extraction method, the copper oxide ore gets the concentrate or crude metal through breaking and grinding, batching, smelting or hydrometallurgy processing, characterized by that the said smelting process is a low temperature sulfurizing roasting and flotation combined process, this kind of process is to grind the copper oxide ore to the graininess that accounts for more than 93% of less than 200 mesh, add 0.5% of the sulphur powder to mix, then put roasting furnace in 250 duC roasting, roasting time 30-40 minutes, at this moment copper oxide and its associated gold and silver turn into the sulphide and break away from matrix of original ore, get artificial copper sulfide ore and send into the flotation again, the flotation adopts the first-stage roughing, the second-stage roughing, scavenging are chosen once separately, the middlings return to the flow of the first-stage and second-stage roughing, produce the concentrate, discard the tailing.

2. A metallurgical process according to claim 1, wherein the copper oxide ore being treated is a low grade refractory ore having a copper grade of less than 1%.