Quais são os tipos de minério de fluorita e como beneficiá-lo?

Fluorite, a vital industrial mineral, is categorized into four ore types based on gangue mineral composition. Each type requires tailored beneficiation methods to maximize fluorite recovery and purity.

Fluorite Ore Type

Os diferentes minerais de ganga podem dividir o minério de fluorite em quatro tipos:

• Minério de fluorite do tipo quartzo
• Minério de fluorite do tipo carbonatado
• Minério de fluorite do tipo barita
• Minério de sulfureto de fluorite

(1) Minério de fluorite do tipo quartzo: Os principais minerais são a fluorite e a quartzoe o teor de fluorite pode atingir 80% a 90%. Contém uma pequena quantidade de calcite, barite e sulfureto.

(2) Carbonate-type fluorite ore: The main minerals are fluorite and calcite. The content of calcite can reach more than 30%, and there is a small amount of quartz, sometimes composed of quartz, calcite, and fluorite-type ore.

(3) Minério de fluorite do tipo barita: The main minerals are barite and fluorite, and the barite content reaches 10% to 40%. It often accompanies this type of ore with pyrite, galena, sphalerite, and other sulfides, and sometimes the range of quartz increases, forming a quartz-barite-fluorite type ore.

(4) Minério de fluorite do tipo sulfureto: A sua composição mineral é a mesma que a do quartzo-fluorite, mas contém mais sulfuretos metálicos e, por vezes, o teor de chumbo e zinco pode atingir graus industriais.

 

Como beneficiar o minério de fluorite?

Atualmente, utiliza principalmente o método de flotação para a beneficiação e purificação de fluorite no país e no estrangeiro.

1. Quartzo-Fluorite

Quartz-type fluorite ore is mainly composed of fluorite (about 85%) e quartz, with only a small amount of calcite, barite, and sulfide.

A chave para a seleção é principalmente a redução do silício nos concentrados.

To separate quartz from fluorite, it is necessary to dissociate the quartz and fluorite monomers through grinding, so grinding is an essential factor affecting the flotation of quartz-type fluorite. If the grinding particle size is too coarse, the conjoined body of quartz and fluorite exists in the product, making the rough concentrate after flotation too high. If the grinding particle size is too fine, although it dissociates the quartz and fluorite individually, it will lead to excessive fluorite crushing in the grinding product and reduce the recovery rate of fluorite.

The most reasonable method is to use a stage grinding process, which can reduce the silicon content in the fluorite concentrate after flotation and increase the fluorite concentrate’s recovery rate.

This type of fluorite ore can be divided into two kinds, coarse-grained and fine-grained, according to the inlaid characteristics of valuable minerals.

• A fluorite incorporada de grão grosso é fácil de selecionar. É utilizado o coletor do tipo ácido gordo, o ajustador de lama é o carbonato de sódio e o inibidor de quartzo é o vidro de água. Pode obter concentrado de fluorite de alta qualidade através de um processo grosseiro e multi-fino.
• The flotation reagents of the fine-grained embedded quartz-type fluorite ore are the same as those of the coarse-grained embedded quartz-type fluorite ore. Still, due to the small embedded particle size of the target minerals, it is necessary to strengthen the grinding and use a stage grinding stage for the separation process flow.

Quartz-type Fluorite Beneficiation

Quartz-type low-grade fluorite ore: the main recoverable mineral is fluorite with a grade of 30%, and the main gangue mineral is quartz, followed by calcite, feldspar, mica, etc.

Parâmetros do processo: rough dressing and grinding fineness is -200 mesh(accounting for 42.52%). It uses water glass + ZN608 as an inhibitor and fluorite low-temperature collector ZN136 as a collector. It uses one coarse, one sweep, and seven fine. One-stage concentrate regrinding and middling return to a closed-circuit process that can obtain fluorite concentrate with a CaF2 grade of 97.45% and a recovery rate of 92.71%.

Fine-grained Embedded Quartz-type Fluorite Ore Beneficiation

O minério de fluorita do tipo quartzo incrustado, de grão fino, tem um teor de fluorita de 32,75%. A relação de incrustação entre a fluorite e o quartzo no minério é complexa e a granularidade de incrustação é pequena. É necessária uma moagem fina para dissociar os monómeros de fluorite e quartzo.

Parâmetros do processo
A investigação experimental adopta o processo de um desbaste, um varrimento e sete beneficiações.

One-stage middling cast tails directly; flotation concentrate of one-stage concentrate regrind and refloat. It uses the self-developed ZN136 as the fluorite low-temperature flotation collector. Under the condition that the slurry temperature is 5~10℃, the beneficiation index obtained by the laboratory is the fluorite feed CaF2 32.52%, the concentrate CaF2 97.55%, and SiO2 1.36%; the fluorite recovery rate is 76.67%. Under the slurry temperature of 5℃, the industrial production index is fluorite feeding CaF2 30.14%, concentrate CaF2 97.37%, SiO2 0.81%, fluorite recovery rate 89.67 %.

2. Calcite-fluorite

Calcite-type fluorite ore is mainly composed of fluorite and calcite (content up to 30% or more), with a small amount of quartz, which can form quartz-calcite-fluorite-type ore.

A principal razão pela qual os minérios de fluorite do tipo calcite são difíceis de separar é o facto de tanto a calcite como a fluorite serem minerais que contêm cálcio com propriedades físicas e químicas de superfície semelhantes.

Both fluorite and calcite are calcium-containing minerals, and their solubility is similar. Therefore, the flotation separation of such ores is difficult. The selection of suitable collectors and inhibitors is the key to achieving the separation of fluorite from calcite. At the same time, proper process flow and process conditions are also essential factors in improving the flotation index. Combined and new agents are widely used in sorting this type of fluorite ore.

To achieve the separation of calcite and fluorite, the pH value of the slurry and use a collector to achieve a good separation effect. Water glass, salted water glass, acidified water glass, sodium hexametaphosphate, lignosulfonate, dextrin, tannin, and calcium carbonate special inhibitor ZN608 can be used. They can use them alone or in combination to inhibit calcite for separation purposes.

 

3. Barite-fluorite

The main minerals of barite-type fluorite ore are barite and fluorite, and the barite content is 10% to 40%. It often accompanies this ore with pyrite, galena, sphalerite, and other sulfide minerals.

The difficulty in beneficiation of barite-type fluorite ore is that the floatability of barite and fluorite is similar, which makes it difficult to separate the two.

Mixing flotation and Na2CO3 adjusts the slurry’s pH value in the flotation of barite-type fluorite ore. It uses oleic acid and water glass as collectors and inhibitors to obtain fluorite and barite. The concentrate is mixed and uses flotation to separate barite and fluorite.

The flotation separation process of barite-type fluorite ore is divided into two types: inhibiting barite from floating out of fluorite and inhibiting fluorite from floating out of barite. The key to flotation separation of barite and fluorite lies in the choice of inhibitor.

Utilização de inibidores combinados 1

Utilizando o ácido oleico como coletor, a dextrina + cloreto férrico como inibidor combinado da barita, através de um processo de flotação grosseiro, um processo de flotação fino, pode obter-se o concentrado de fluorita com um grau de CaF2 de 97,87% e uma taxa de recuperação de 79,26%, o concentrado de barita com um grau de BaSO4 de 94,62% e uma taxa de recuperação de 72,53%.

 

 

Utilização de inibidores combinados 2

O ZN608 pode inibir seletivamente a barita, e o vidro de água pode inibir seletivamente o quartzo e melhorar a dispersão da polpa. O sulfato de alumínio pode não só ajudar na inibição da barita, mas também enfraquecer o efeito inibidor do vidro de água na fluorita. Para atingir o objetivo de inibir a barita e o quartzo ao mesmo tempo.

Parâmetros do processo: The mixed concentrate was treated with one coarse, four refined, one sweep, and selected medium ore returning to the process. It can obtain the fluorite concentrate with a CaF2 grade of 97.21%, a recovery rate of 85.44%, and a BaSO4 grade of 94.36%, and the barite concentrate with a rate of 86.75% and a density of 4.25 g/cm3 has achieved high-efficiency separation of fluorite and barite.

4. Beneficiamento de minério de sulfeto de fluorita

A composição do minério de fluorite do tipo sulfureto é semelhante à do mineral de fluorite do tipo quartzo. No entanto, o teor de sulfureto de metal é mais elevado, e por vezes o teor de chumbo e zinco pode atingir o grau industrial. Portanto, ao desenvolver e utilizar a fluorita, devemos também considerar a recuperação do minério metálico.

As minas de fluorite do tipo minério de sulfureto utilizam geralmente colectores de minério de sulfureto para selecionar preferencialmente os minerais de sulfureto metálico e, em seguida, utilizam colectores de ácidos gordos para recuperar a fluorite dos rejeitos de flotação. Além disso, também pode utilizar processos como a torrefação e a lixiviação para extrair metais valiosos e decompor a fluorite. O fluxo do processo é relativamente simples e podem ser preparados produtos de fluorite de alta qualidade, reciclando simultaneamente metais valiosos de forma abrangente.

 

Resumo

Fluorite ore is classified into four types based on gangue mineral composition: quartz-type, carbonate-type, barite-type, and sulfide-type, each requiring tailored beneficiation approaches. Quartz-type fluorite focuses on silicon reduction through staged grinding and selective inhibitors, while carbonate-type demands precise pH control and specialized reagents to separate calcite. Barite-type fluorite relies on combined inhibitors like dextrin-ferric chloride or ZN608 for efficient separation from barite. Sulfide-type fluorite prioritizes sequential flotation to recover metals before fluorite extraction. Across all types, optimizing grinding, reagent selection, and process flow ensures high-purity fluorite concentrates with maximal recovery, highlighting the importance of ore-specific strategies in industrial mineral processing.