FI74893C - FOERFARANDE FOER SELEKTIV FLOTATION AV SILIKAT-CARBONATMALMER. - Google Patents

Description

1 74893

The present invention relates to a process for the flotation flotation of silicate-5 carbonate-containing mineral slurries obtained by flotation, which precedes the acid flotation circuit for the separation of dosing-like or other flotability properties of the same mineral group. The method removes minerals that interfere with separation flotation in an acidic flotation silicon. The invention is a particularly suitable pretreatment step before separation flotation in an acid circuit for a mineral slurry obtained by flotation containing limestone. The invention makes it possible to utilize the feed of the entire flotation circuit so that the selectivity of the process and the supply of valuable minerals to the concentrate are high.

It is known that silicate minerals can be separated from limestone by foaming using a cationic collector, thus obtaining both pure limestone concentrate and pure silicate co-concentrate, which is still suitable for the separation flotation of different silicates in an acid circuit. Due to the nature of the method, it has the following disadvantages: 25 - in silicate-limestone separation flotation with a cationic collector, the yield loss of silicates is high; - silicate flotation products of silicates cannot be used in further processes; 30 - in the re-flotation of the silicate co-concentrate, in the pursuit of a limestone-free silicate co-concentrate, the yield of silicates is high; - in order to achieve a higher yield of silicates in the silicate co-concentrate, the limestone content 35 of the concentrate rises so high that the separation foaming of the different silicates in the acid circuit is no longer successful or is otherwise unprofitable.

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My research, I have found "that silikaattikarbo-naattipitoisten mineral slurries esikäsittelymenetelmäl performed before the above-acidic various silicate minerals separation flotation circuit provides the following benefits: 5 - silikaattiyhteisrikaste obtained and silicate karbonaattierotusvaahdotuksessa kationisel the collector-la-tiriperikasteet silicate can be utilized in various silicate minerals separation flotation in acid circuit; The 10 - method gives a silicate co - concentrate with a uniform limestone content and a low limestone content, which is suitable for the separation flotation of different silicates in an acid circuit; - the yield of silicate minerals in the pretreated silicate compound concentrate is high; - due to the low limestone content of the mineral sludge pretreated according to the method, the amount of acid required for the separation flotation of the different silicates in the acid circuit is small and thus the amount of harmful by-products 20 is also small;

To illustrate the invention, the following illustrative examples are provided.

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Example 1

From the wollastonite-limestone ore used as a test material, the silicate co-concentrate and silicate pellet concentrates foamed with a cationic collector 30 were combined by a previously known method. The yield of wollastonite in the flotation to this combined slurry was 100.0%. The foamed yield of the other silicates was 92.4%. 35 The combined silicate slurry was then prepared according to a developed method to remove previous collector coatings from mineral surfaces with sodium hexametaphosphate.

II

3,74893 accounts 5 min. Sodium hexametaphosphate was used at 500 g / t. The slurry was then prepared with tall oil fatty acid for 5 min. Tall oil fatty acid was used at 2000 g / t, 5

In the flotation step of the process, wollastonite went into a sub-fraction with other silicate minerals, whereby the yield of wollastonite to the sub-fraction was 95.0%. Most of the limestone went to the over-fractionation of the foam, so that the under-fraction contained 1.2% CaCO2,

After the pretreatment step according to the method, the flotation subfraction was subjected to wollastonite-silicate separation flotation in an acid circuit as before, with a final wollastonite concentrate of 97.0% CaSiO 2 and a wollastonite yield of 75% of wollastonite concentrate the total flotation yield was 81.2%.

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Example 2

The steps in Example 1 were repeated so that the sludge separation prior to the silicate-calcite separation flotation was omitted. In the training step, 2500 g / t of tall oil fatty acid was used.

In the flotation step of the process, the yield of wollastonite in the alite-30 fraction was 93.0% and in the alite fraction was 1.7% CaCO 3.

After the pretreatment steps according to the method, wollastonite-silicate separation flotation in an acid circuit gave a wollastonite concentrate with 95.0% 35 CaSiO 3 and the yield of wollastonite to the wollastonite concentrate was 8 * 1.0%. The total yield of wollastonite calculated from the feed was 77.3%, which was the same as the total flotation yield I.

t 74893 because no sludge separation was performed.

As can be seen from the above examples, high quality concentrates can be prepared by applying the process of this invention, e.g., prior to wollastonite-silicate separation flotation in an acid-flotation circuit, while the high mineral content of the mineral concentrate becomes high. When considering the uptake of wollastonite into wollastonite concentrate, it should be noted that with a conventional flotation method using a cationic collector, the uptake of wol lastonite before wollastonite-silicate separation foaming feed is at best 70.0%, i.e. the total yield of wollastonite is 60% 15

The examples given are not limiting in terms of the reagents used and their amounts, etc., but these must, of course, be chosen to be suitable for each type of ore.

Sodium hexametaphosphate has been used to dispose of aggregate coatings from mineral surfaces, but other suitable substances or compounds as well as other suitable methods may be considered.

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Tall oil fatty acid has been used as a collector, but other collectors may also be considered depending on the minerals to be foamed.

Claims (2)

A process for the preparation and foaming of silicate-carbonate-containing mineral sludges obtained by flotation, characterized in that it comprises the following steps: - separating foaming of minerals similar in terms of frothing properties 10 - in the training step the previous collector covers are removed from the mineral surfaces - in the flotation step the minerals which interfere with the separation Process according to Claim 1, characterized in that the previous collector coatings are disposed of on the surfaces of the minerals by a dispersant, or by an organic or inorganic acid or base, or by some other chemical or physical means.