Native gold - arsenic ore containing 1-2% to 10-12% arsenic pyrite. In other sulfides, there are often pyrite and sometimes pyrrhotite. In rare cases, minerals do not contain particulate gold. Such ores can be treated by cyanidation or by flotation followed by cyanidation of the flotation concentrate. Most of the gold in the ore is often encapsulated in sulfides in the form of fine particles. For this type of ore, mixed flotation can be carried out to select gold - arsenic concentrate or gold - arsenic - pyrite concentrate. The concentrate is calcined, and the calcined slag is treated by cyanidation or sent to a smelting plant for smelting. An arsenic-containing product is obtained during the firing. However, the current demand for such products is small. If the waste tailings cannot be obtained after the mixed flotation, the flotation tailings may be cyanated or the ore may be cyanated, and the gold-containing sulfides may be recovered from the cyanide tailings by flotation.

When flotation of gold - arsenic ore, it is necessary to test the known methods, namely, stage flotation, flotation of ore and slime separately, flotation in soda medium, etc., in order to improve the flotation process of gold - arsenic ore. Various indicators. When flotation of arsenopyrite, oxygen must be added to the slurry. The broken iron formed during the grinding process acts as an absorbent for oxygen. When soda ash is present, the oxidation of iron and the absorption of oxygen proceed slowly. Therefore, when formulating flotation conditions, the amount of soda added in the mill should be tested (consumption of 1~2 kg / ton) so that the pH of the mill can reach 10~10.2 , and then Reduce it to 8.5~8.8 when flotation . Copper sulfate is useful as an activator advantageous in an amount of 100 to 200. g / ton. This medicine should be added to the sweep. In individual cases, the recovery of gold and arsenic will increase as the slurry and the mixing time of the collector increase (up to 20 to 30 minutes).

Sometimes it is appropriate to use a preferential flotation to sort gold-containing pyrite concentrates and arsenic concentrates, or single - gold - pyrite concentrates. If the gold in the pyrite concentrate and the arsenic concentrate is recovered by different methods or if a high-crystal arsenic concentrate is required, it is advantageous to separately select the pyrite concentrate and the arsenic concentrate. Only single - gold - pyrite concentrates can be selected under the following conditions :

When the flotation tailings meet the requirements of the scrap gold grade, and arsenic has no industrial value;

The gold in the flotation tailings is not the same as the gold in the pyrite concentrate, which can be recovered by cyanidation.

Using lime or lime with air in an oxidation medium, inhibition arsenopyrite soft manganese ore and potassium permanganate, can arsenopyrite and pyrite separation. In many cases, the effectiveness of the oxidant depends on how well the oxidant use system is formulated and adhered to. The amount of oxidant used is too large, and the contact with the slurry for too long will cause the activation of arsenopyrite.

Difficulties in flotation of mud ore and carbonaceous ore. Mineral deposits usually contain carbonaceous materials, various shale and carbonates. When flotation of sulfides, these components enter the concentrate, which increases the yield of the concentrate and reduces the quality of the concentrate. In addition, the slime can absorb the flotation agent and hinder the flotation of the sulfide. In order to study argillaceous ore, it is first necessary to determine the gold content in the ore and to test the following methods according to its quality:

Desliming of ore and its processed products (rough selection of tailings, intermediate products, sweeping concentrates). If necessary, the separated slime should be subjected to adsorption cyanidation;

Use different chemicals ( KMLI , IIAA , aniline dyes, starch, etc.) to inhibit slime floatation in rough, sweep or select operations;

Flotation and treatment of the ore portion with the agent.

The industrial utilization of arsenic pyrite concentrate and pyrite - arsenic pyrite concentrate containing fine particle impregnated gold has not yet been resolved. This problem is difficult to solve due to the limited demand for various compounds of arsenic and the toxicity of these compounds.

Arsenic is a harmful component in the pyrometallurgical process, so it is sent to concentrates in smelters; there are strict limits on the content of arsenic.

In foreign production practice, the gold - arsenic concentrate is generally calcined, and then the calcine is treated by cyanidation. When using these methods, you need to be carefully collector arsenic from the gas phase, if the product sales arsenic poor, but also it takes high cost or it may be stored or buried. It is best to use two-stage roasting: the temperature of the I- stage roasting is 500~ 5800C And give a small amount of air, the second stage roasting temperature is 600~620Y3 and give a lot of air. Only in this way, it is possible to form a fusible compound at the time of firing, and to obtain a calcine having good porosity. The arsenic grade in the accompanying sand should not exceed 1~1.5% . If a segment for firing at a higher temperature and to an excess air condition, because it will generate less volatile arsenate (e.g. iron arsenate FeAsO 4) to improve the arsenic grade of the calcine. Arsenate covers the surface of gold and hinders the dissolution of gold during cyanidation. When roasting a material containing realgar ( AsS ) and orpiment ( As 2 S 3 ), iron arsenate is formed to a large extent. At a temperature of 600~ 620 °C The second stage of calcination carried out is mostly chlorination roasting or oxidative - chlorination roasting. In most cases, the gold encapsulated in pyrite or arsenopyrite can be more fully exposed by this calcination.

When calcining a carbon-containing gold - arsenic concentrate, it is best to carry out in two stages: at a temperature of 500~ 600 °C And an air intake under low to be - of paragraph calcination at a temperature of 650 to 700 °C And the second section to the excess air firing. - of segments should be fired to burn arsenic content of the calcine is less than 1%, while the second stage should be calcined activated carbon and sulfur burn. In order to burn off the activated carbon, it is necessary to feed not only excess air but also a relatively high temperature, and it takes a considerable amount of time. When calcined in a boiling roaster, the calcination process proceeds faster and the calcination is more complete. In order to achieve self-ignition roasting without fuel in the roaster, the concentrate should have a sulfur content of 22 to 24% .

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Maximum load: 2000kg

Used to transfer materials overhead, our Light Girder Suspension Crane is especially suitable for use in workshop that have low ceilings as well as factories and sites made of lightweight steel frames where the bridge crane reaches its limit.

The modular design contains fewer standard parts that make crane assembly as easy as stacking blocks. With these modular parts, users can reassemble a new crane, according to the change in lifting requirements of the alterations made to the workshop.

Due to the ultra-light weight of the crane, there is little friction between the trolley wheel and the rail. Easily moved by hands, this suspension crane can move clumsy, heavyweight workpiece in a fast manner. Available also with the mechanical electrical chain hoist, hoist drive, electrical control device, and matched system, the crane requires limited maintenance and has a long service life.

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Optional Parts

Aluminum rail

Railway turnout

Elevating platform

Power supply device

Electrical travel drive system

Flexible Girder Crane

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