Antimony ore dressing method

The rough selection of antimony ore beneficiation is generally carried out by re-election method. The selection is by re-election, flotation, electromagnetic selection or combined metallurgy. It is used to treat ore with a large content of fine ore or raw mud. efficient grinding and classification equipment to reduce tantalum niobium clay minerals.

The commonly used collectors for flotation are fatty acids, tannins, phosphonic acids, hydroxamic acids, cationic collectors, etc. The environmental pollution of the collectors and the cost of the chemicals are of paramount importance.

    I. Mineral processing characteristics of antimony ore

Niobium iron ore - Chemical Formula tantalite of AB ₂ O _6, both referred niobium tantalite. A is iron and manganese , and B is strontium and barium. The magnetic susceptibility of the coltan-niobite is (22.1 to 37.2) × 10-6. The tantalum iron has a dielectric constant of 10 to 12 and the tantalite has a density of 7 to 8. The density of minerals is 5.15 to 8.20 (increased as the content of strontium increases).

Second, antimony ore dressing technology

Yankuang ore dressing generally adopts re-election to discard most of the gangue minerals and obtain low-grade mixed coarse concentrates. The coarse concentrate minerals entering the selected operations are complex in composition and generally contain a variety of useful minerals. A variety of beneficiation methods such as re-election, flotation, electromagnetic selection or combined metallurgy are selected to achieve separation of a variety of useful minerals.

(1) Foreign ore dressing

It is essential to wash ore in the processing of ore with a large content of fine ore or raw mud. Australia's Grinbus mine weathered pegmatite alluvial clay rough selection plant, set up two washing system, the original mine with a diameter of 1.5m, a pore size of 10mm cylindrical sieve twice after washing, selected under the sieve, sieve large and The clay ball is ground into a self-grinding mill for about 4 mm, and then sieved with a cylindrical sieve having a hole diameter of 10 mm. The material under the sieve is selected, and the material on the sieve is discarded or returned for regrind. The washing water consumption is 5m ³ /t, and the cylindrical sieve processing capacity is 350 tons/hour.

Foreign smelting and mining plants attach importance to the use of high-efficiency grinding and grading equipment to reduce the muddy of strontium minerals. Good results were obtained from the surrounding pebble rod mill and vibrating screen closed circuit in the original pegmatite roughing plant of the Greenbus mine. The Borneo Lake antimony mine in Canada has been continuously improved and the current grinding process is very distinctive. The mine is closed with a Ф2.4m×3.6m Marcy-type lattice ball mill A-C horizontal vibrating screen (straight screen), the sieve size is 2.5mm, and the sieve is graded by 0.2mm with Derrick sieve, -2.5+0. The 2mm grain grade is selected by a spiral concentrator, and the tailings are dehydrated by a curved sieve and returned to re-grind. The ball mill has two kinds of products to form a cycle, that is, a two-stage closed-circuit grinding is realized by one mill. After the adjustment of the grinding circuit, the cyclic load rate is usually about 180%, and the cyclic load is small and easy to form excessive pulverization.

The rough selection of coltan ore in foreign countries is still mainly based on re-election, and more efficient re-election equipment is used , and the process is simple. For example, the Grimbs mine directly uses a jig for rough selection of -10mm ore. The re-election-flotation-re-election process formed in the 1980s in Bonn Lake, Canada, is becoming more and more perfect. The process is still dominated by re-election, and flotation is only used to treat fine mud. The re-election equipment used GEC spiral concentrator, 3-layer suspended Dyest shaker, Holman slime shaker, and cross-flow belt concentrator. The former Soviet Union used flotation to separate the coltan, fine-grain and topaz in the re-selected concentrate. The collector was hydroxamic acid, the regulator was oxalic acid, and it was floated in hydrochloric acid medium (pH 2). When Ta ₂ O _{5 is} contained at 2.52%, the concentrate grade is 27% and the recovery rate is 90%.

(2) Domestic ore dressing

1, rough selection of antimony ore

The ore grade of domestic antimony ore is generally low, and its minerality is brittle and dense. In order to ensure the grinding size and avoid over-grinding, the stage grinding stage selection process is generally adopted. Jiangxi Yichunyu Concentrator uses a horizontal curved screen instead of a linear vibrating screen for screening. The on-site exploration test results show that the fineness on the sieve can be reduced by 14.70%, the coarseness under the sieve can be reduced by 4.3%, and the screening efficiency can be increased by 17.72. %. The successful test of this equipment provides a new way for the field of grinding and screening. Fujian Nanping is a large granitic pegmatite deposits in 1998 by the Guangzhou Research Institute is a non-ferrous metal ores experimental study of the dressing, designed to provide the basis for the construction, dissemination characteristics based on tantalum, niobium and cassiterite mineral grain size, proposed the use of Stage grinding, stage selection process. A section uses a rod mill and forms a closed circuit with the screen to reduce over-grinding. The second-stage grinding uses a ball mill and forms a closed circuit with the high-frequency vibrating fine screen. In addition to strictly controlling the particle size, it can also increase the processing capacity and improve the grinding efficiency. The mine is rough selected using a single re-election process. The re-election equipment has a GL spiral concentrator, a spiral chute and a shaker. The ore is selected from the original ore containing (TaNb) 2O5 0.0499%, Sn 0.0598%, and the crude concentrate obtained after rough selection has a yield of 0.248%, containing (TaNb) ₂ O514.94% (including Ta ₂ O ₅ 10.79%), The recovery rate of raw ore is 74.30% (the recovery rate of Ta ₂ O ₅ is 74.96%); the content of Sn is 15.71%, and the recovery rate of raw ore is 65.11%.

2, Yankuang selection

The coarse concentrate obtained by the rough selection process is generally a mixed coarse concentrate, which needs to be further selected to separate a variety of useful minerals. For example, Fujian Nanping 钽铌 selects the surface of the mineral with 6% hydrochloric acid solution, then removes the strong magnetic minerals and iron filings by weak magnetic separation, dries and sieves into three levels of +0.2, +0.1 and -0.1mm. The bismuth concentrate was obtained by one-time rough selection and one-time sweeping using a dry magnetic separator. The selected results: 764 钽铌 concentrate yield 0.0764%, containing (TaNb) ₂ O ₅ 45.64% (Ta ₂ O ₅ 32.57 %), the recovery rate of raw ore is 69.92% (Ta ₂ O ₅ recovery rate is 69.071%), and the recovery rate of selected operations is 94.11%;

3. Fine-grained ore flotation

The No. 69 ore body in the Dajishan tungsten deposit in Jiangxi Province is a large-scale strontium-tungsten-rich granite ore body. The size of the strontium iron mineral in this mine is very fine, and most of the grain size is 40-74 μm, so the conventional re-election is adopted. The method has a low recovery rate of ore dressing and a recovery rate of only 25% to 33%. The Guangzhou Institute of Nonferrous Metals uses a heavy-floating combined process to recover strontium minerals. When the flotation feeds Ta ₂ O ₅ 0.0145%, the flotation concentrate yield is 0.7%, and the concentrate contains Ta ₂ O ₅ 1.8%. The recovery rate is 87%, and the concentrate enrichment ratio is more than 100 times. Then re-select the enrichment and separate the antimony and tungsten from the water. The recovery rate of smelting and smelting is 44%.

The ore properties of the Baiyun Obo mine in Baotou are very complicated. In particular, the strontium minerals are famous for their poor, fine and difficult selection. The Guangzhou Institute of Nonferrous Metals uses the flotation method to enrich the rare earth flotation tailings with strontium minerals, using Pb ( NO ₃ ) ₂ is an activator, D-1 is an inhibitor of calcium minerals, a combined collector mainly composed of hydroxamic acid, flotation flotation in a medium of pH 6, and flotation-enriched coarse ore concentrate After desulfurization, it is selected by the weak magnetic-shaker process to obtain iron-rich concentrate and iron concentrate. Fushun Iron Concentrate 1 contains Nb ₂ O ₅ 1.66%, Concentrate 2 contains Nb ₂ O ₅ 0.59%, and the total recovery of rhodium is 35.58%. After Chen Quanyuan et al. studied the rare earth flotation tailings in the Bayan Obo mine, it was proposed that after the concentrated desilting of the rare earth flotation tailings, the oxidized wax soap, water glass anti-floated fluorite and residual rare earth minerals were added, and the products in the tank were concentrated. After adding ammonium fluorosilicate, oxide wax, flotation iron mineral to obtain iron concentrate, iron tailings plus sulfuric acid, carboxymethyl cellulose, salicyl hydroxamic acid, C5-9 hydroxamic acid and oxalic acid, once Rough selection and three times of selection of bismuth flotation concentrate containing Nb ₂ O ₅ 1.67% and recovery rate of 40.14%, the concentrate is further separated by iron and bismuth by strong magnetic, and bismuth concentrate and magnetic products of non-magnetic products are obtained. Yuci concentrate.

  Current Situation and Progress of flotation reagents three-Ta-Nb ore

(1) 钽铌 mineral collector

The most effective collectors for antimony ore are fatty acids, tannins, phosphonic acids, hydroxamic acids, and cationic collectors.

1, the former Soviet fatty acids collector clopidogrel Grad Gehennas gold oxide ores have been used for two collector: oleic acid, sodium oleate, sodium tridecyl, sodium tallow alkyl sulfate, sodium phosphate and isooctyl A detailed study of the floatability of coltan-niobite. Tests have shown that when using fatty acids as collectors, the trapping ability of saturated hydrocarbon groups is worse than that of unsaturated ones. When the pH value is 6-8, the flotation of coltan-anthalite with sodium oleate is very effective, and it is inhibited in both strong acidic medium and strong alkaline medium. Modification of fatty acids can improve their selective capture. For example, a new effective reactive group sulfonic acid group, polycarboxyl group, sulfuric acid group, halogen, amine (amino) group, aminoacyl group, amide group and the like are introduced into the molecule.

2. Tannic acid collectors Tannic acid can form strong surface compounds with rare metal minerals such as strontium and barium. The hydrocarbon group is outward and the mineral is hydrophobic. However, this chemical adsorption does not exist with gangue minerals, so the collection ability is strong and the selectivity is good. The disadvantage is that there are pollution problems in the production and use of bismuth-containing substances. Benzyl phthalic acid and toluic acid are effective collectors for strontium minerals. The combination of citric acid and xanthate can greatly improve the recovery rate of strontium minerals.

3. The study of the use of bisphosphonic acid to collect ruthenium rutile by phosphonic acid collector shows that bisphosphonic acid is a good collector of ruthenium rutile when the pH value of the slurry is 2 to 4, and the recovery rate reaches 90.87%. ~91.70%, at the same time, it is believed that the bisphosphonic acid is adsorbed on the surface of the ruthenium rutile, and the adsorption form is mainly chemical adsorption.

4. Hydroxamic acid collectors The industrial hydroxamic acid used in some fine earth mines in China is equipped with transformer oil for rough selection. When the ore contains Nb ₂ O ₅ 0.094%, the crude concentrate grade Nb can be obtained. ₂ O ₅ 0.9 to 1.0%, and the recovery rate is about 90%.

5. Cationic collectors Studies have shown that laurylamine acetate can effectively float limonite minerals in neutral media.

6. Other collectors The use of the new agent N ₂ for the capture performance of strontium minerals shows that N ₂ of the high carbon chain is an effective collector for strontium minerals. Good results were obtained by flotation of the Bayan Obo ore with N-nitrosophenylamine. The exploration experiments in the former Soviet Union showed that the hydrocarbyl sulfate was also suitable for the flotation of the coltan-tantalite in the pegmatite deposit.

Many flotation agents, especially collectors, are not ideal when used alone. However, when some agents are used in combination in a certain proportion, the effect is not a simple additive effect, but a synergistic effect, that is, 1+1. >2 synergy effect. Such as xanthate and hydroxamic acid combined flotation copper oxide; sodium oleate and hydroxamic acid combined flotation of andalusite ; tannic acid and xanthate mixed, copper iron spirit mixed with benzoic acid, benzoic acid and The mixture of Tal soap and flotation of black tungsten fine mud; F ₂ O ₃ mixed with salicyloxyphthalic acid and flotation of cassiterite fine mud have achieved good results.

(2) Antimony ore flotation regulator

The main gangue minerals of antimony ore are silicate minerals, fluorite and carbonate minerals. Typical inhibitors of these minerals are water glass, sodium hexametaphosphate, starch, pyrophosphoric acid, sodium hydrogen phosphate, sodium lignosulfonate, tannin, lactic acid, citric acid, tartaric acid, and the like. The pH value has a great influence on the flotation process, and the modifiers commonly used for adjusting the pH value include sulfuric acid, hydrochloric acid, sodium hydroxide, and soda.

(III) Analysis of problems existing in antimony ore flotation

1. Collection of collectors. The molecule contains functional groups -COOH, -SO ₄ H, -SO ₃ H, which have strong collection ability and poor selectivity, and are only suitable for the fine mud with a simple flotation mineral composition and quartz as the main gangue. Hydroxamic acid has a weaker ability to capture fine mud than fatty acids, but it is better. Phosphonic acid has a strong ability to capture antimony ore.

2. Environmental pollution of pesticides and cost of pharmaceuticals. Tannic acid can form a strong surface compound with metal ore such as strontium and barium. The hydrocarbon group is outward and makes the mineral hydrophobic. However, this chemical adsorption does not exist with gangue minerals, so the collection ability is strong and the selectivity is good. Ca ^{2 +} and Mg ^{2 +} ions are not sensitive and have strong adaptability to ores with high calcite . However, citrate is highly toxic and may cause environmental pollution. In the fine mud flotation, the dosage is large and the price is high. At the same time, some of the chemicals are more toxic and need to increase environmental protection costs, thereby increasing the cost of mineral processing. When using hydroxamic acid flotation, the effect is better, but the amount of the agent is larger.

In recent years, the domestic research on flotation flotation has made some progress. However, due to the high price of pharmaceuticals, only a few foreign mines have adopted flotation methods, such as the Canadian Oka Concentrator and the Brazilian Araksa Mine.