DE3107305A1 - Process for flotation of a mineral - Google Patents

Abstract

The invention relates to a process for flotation of a mineral in which the flotation of the mineral is carried out with the use of at least one oil of vegetable origin. The oil can be sunflower oil. The mineral is suitably coal.

Description

The invention relates to a method according to the preamble

of claim 1, and in particular a method for foam flotation.

The process of foam flotation has already been used for separation used by coal from gangue material such as shale and pyrite. It will generally first the coal is broken and sifted and then the sifted fine coal placed in a flotation tank after the coal with a foaming agent and has usually been treated by a collector agent. Examples of previously used Foaming agents are alcohols. Kerosene and fuel oil are used as collection agents or Collectors used.

The invention relates to the use of a plant of vegetable origin in the flotation of minerals. In particular, the invention provides a method created for the flotation of minerals, in which the flotation of the mineral under Use of at least one oil of vegetable origin is carried out.

A specific example of an applicable vegetable oil is sunflower seed oil of the Helianthus-Onnuus species. Other oils are for example Corn oil, soybean oil and cottonseed oils.

The mineral subjected to froth flotation can be broken coal be. For example, the mineral, such as coal, is broken or crushed and to a water suspension (for example with a concentration of 5 to 20 % By weight) and the vegetable oil and a foaming agent are added. Thereafter air can be blown through the slurry while it is stirred or

is agitated. The hydrophobic particles of the coal cling to the air bubbles formed in the slurry and are of these carried to the surface from which they are stripped. The slate (the one has a high content of inorganic minerals, i.e. ash) remains through the chemical Reagents essentially unaffected and since it is heavier, it sinks to the Bottom of the slurry and can be removed. Usually can be a coal concentrate can be achieved that contains an ash content down to 5 to 10 wt .-%.

The vegetable oil has the advantage that it can be produced in the country so that it is not subject to any of the restrictions that may arise from time to time with mineral oils such as kerosene and fuel oil.

In the case of coal, the process can be used to separate two parts of the floating material or flotations are used, one of which is used to supply steel mills is suitable and has a low ash content of about 10%, while the other is suitable for supplying power plants and has an ash content of 15 has up to 20%. The coal can be subjected to a first froth flotation in order to to give a concentrate (a coarser foam) which can then be floated again can. The re-floated concentrate (referred to as "purer" flotation), can produce a second foam concentrate (a "cleaner" foam) that can be used is suitable in steel works. The outflows from the second foam concentrate (the "purer Outlets ") can be used in the power plant.

The invention is described below by way of examples explained in more detail on the drawing; the single figure of the drawing shows schematically an embodiment of double flotation according to the invention.

According to the drawing, raw coal is washed and the coarse coal is delivered to a power plant and a steelworks.

The washed coal fines are subjected to the first flotation, the first flotation outflows are effectively waste. The foam concentrate obtained is subjected to a second flotation. The second foam concentrate can be used for the Steel smelter can be used while the wastes are delivered to the power plant can.

Various investigations were carried out to assess the invention, using two different methods. The procedural measures for Examples 1 through 5 are given below: PROCEDURE I Carbon first sieved with a 0.8 mm sieve to remove the coarse parts. 200 grams will be placed in a cell of a DENVER laboratory flotation device and it becomes water added so that a total pulp volume of 2,000 ml results. The mechanical one Agitator or stirrer of the device is sunk into the pulp, then started and set to a speed of about 1,800 rpm. Then one becomes mandatory Amount of collector or collector agent and a foaming agent added and the agitation or stirring is continued for exactly 3 minutes (conditioning period), At the end of this period, air is forced into the pulp through the agitator blades. The bubbles created in this way carry the coal particles to the surface on which they are stripped and collected in a shallow dish.

The flotation time is 1 to 3 minutes. The collected coarser Foam is slurried with additional water to a solids content of 4 - 7% then placed in the same DENVER flotation cell. Then the agitator is in Put the porridge in and start and it gets right away thereafter Air is forced into the slurry, after which the foam produced is stripped and collected will. The second flotation is also carried out for a period of 1 to 3 minutes executed. The purer foam is collected and the ones left in the cell Cleaner waste is filtered, dried, weighed and examined for ash content.

PROCEDURE II Procedure I is carried out with the exception that a small amount of the same collector / foaming agent of the purer flotation 0.5 minutes before the introduction of air is added.

Various experiments were carried out according to these procedures, and with (a) a mixture of 90% by weight of sunflower oil and 10% by weight of methyl isobutylmethanol (hereinafter referred to as M.I.B.C.); and (b) with 100% by weight sunflower oil (i.e. without the addition of foaming agents).

The experiments and their results are given below: The Examples 1, 2 and 3 are flotation tests with sunflower oil. The examples 4 and 5 are trials with kerosene plus M.I.B.C. (Control). A comparison of the two Tests show that the vegetable oil gives similar results to them can also be achieved with the petroleum product.

EXAMPLE 1 90% sunflower oil and 10% M.I.B.C .; it became the procedure I used. 600 grams of fine coal with 33% ash content and 0.8 mm size were divided into three equal parts of 200 grams each and each with 0.06 resp.

0.08 or 0.10 grams of floating agent fluted (equivalent to 0.3 or 0.4 and 0.5 kg / ton). The results below show that the yields are substantial contained less ash.

Reagent additive For the 1st flotation 0.06 grams 0.08 grams 0.10 grams For the 2nd flotation nothing nothing nothing Yields by weight ash weight ash weight Ash%%%%%% coal in 1.

Foam - coarser 37.9 11.4 46.5 12.1 58.5 13.4 Non-floated coal in a cleaner fleet 25.3 13.3 26.7 14.9 27.8 18.8 Coal in the 2nd

Liquor 12.6 7.6 19.8 8.2 30.7 9.4 EXAMPLE 2 90% sunflower oil and 10% M.I.B.C. using method II.

600 grams of fine coal with an ash content of 33% and a size of 0.8 mm were divided into three equal parts of 200 grams each and each floated with 0.06, 0.08 and 0.10 grams of reagent, respectively. For the second flotation of the 0.02 grams (0.10 kg / ton) of reagent was also added to the foam. That was performed for each attempt.

The results given below show the second in the foam Flotation produces more coal with a low ash content than with Example 1.

Reagent additive For the 1st flotation 0.06 grams 0.08 grams 0.10 grams For the 2nd flotation 0.02 grams 0.02 grams 0.02 grams Yields by weight Ash by weight Ash weight% ash%%% z%% coal in 1.

Flotation-coarser 41.0 11.9 41.8 11.6 56.3 14.0 Non-floated coal in a cleaner fleet 15.4 17.3 12.8 17.2 17.9 21.3 coal in 2.

Foam 25.6 8.7 29.0 9.1 38.4 10.6 EXAMPLE 3 100% sunflower oil using method I.

There were 600 grams of fine coal with 33% ash content and 0.8 mm Size divided into four equal parts of 200 grams each and with 0.10 and 0.12 respectively or 0.14 or 0.16 grams of reagent floated (equivalent to 0.5, 0.6 or 0.7 respectively.

0.8 kg / ton). The results given below show that the Sunflower oils in addition to their effectiveness as a collector or collector behave as effective foaming agents. The yield and ash content is that of des Similar to example 2 if a second flotation is used additional Reagent is added.

Reagent additive For the 1st flotation 0.10 grams 0.12 grams 0.14 grains 0.16 Graitm For the 2nd flotation nothing nothing nothing nothing Yields by weight ash Ash by weight Ash by weight%%%%%%%% coal in 1.

Flotation coarser 41.4 12.4 41.3 12.6 45.8 13.2 50.5 13.9 Not floated Coal in purer fleet 17.9 17.1 17.8 17.4 18.7 18.2 18.7 19.6 Coal in 2nd

Foam 23.5 8 <8 23.8 9.0 27.1 9.8 31.8 10.5 EXAMPLE 4 90% kerosene and 10% M.I.B.C. using method I. 600 grams of fine coal with 33% Ash content and a size of 0.8 mm were divided into three equal parts of each 200 grams divided and each with 0.10 or 0.12 or

0.14 grams of reagent floated. The following results were obtained: Reagent additive For the 1st flotation 0.1 gram 0.12 gram 0.14 gram For the 2nd flotation nothing nothing nothing Yields by weight - ash weight - ash weight - ash %%%%%% Coal in 1.

FlotationRöber 53.8 14.4 66.3 16.2 70.2 16.4 Non-floated coal in a cleaner fleet 49.3 14.9 52.4 18.2 48.8 19.6 coal in 2.

Fleet 4.5 8.8 13.9 8.8 21.4 9.1 EXAMPLE 5 90% kerosene and 10% M.I.B.C. using method II. 600 grams of fine coal with 33% ash content and 0.8 mm in size were divided into three equal parts of 200 grams each and each with 0.10 resp.

0.12 or 0.14 grams of reagent floated. For the second flotation of the An additional 0.02 grams of reagent was added to the foam. It became the following Results obtained: reagent addition For the 1st flotation 0.1 gram 0.12 gram 0.14 Grams For the 2nd flotation 0.02 grams 0.02 grams 0.02 grams Yields by weight - ash Weight - ash weight - ash coal in 1.

Flotation-coarser 53.0 13.5 67.0 16.0 71.0 16.7 Unflotated coal in a cleaner fleet 37.0 15.6 41.4 20.1 37.2 22.6 coal in 2.

Fleet 16.0 8.6 25.6 9.3 33.8 10.3 EXAMPLE 6 - Pilot Plant Operation Comparison of sunflower seed oil as a coal flotation agent - with and without M.I.B.C. to a kerosene-M.I.B.C. mixture (control): carbon fines (0.5 mm) from the Mine A were placed in water in a tank to a solids content of 10 percent by mass slurried.

The coal slurry was at a flow rate of 15 liters pumped per minute into a conditioning tank with a capacity of 85 liters, which is a nominal Residence time of 6 minutes resulted. The flotation agent was continuously in the Conditioning tank pumped. The slurry was then poured into a series of 8 flotation cells introduced each of which had a volume of 11 liters. The foam became continuous stripped from each cell and collected separately from the outlets.

The following reagents were used: (i) Kerosene with methyl isobutyl methanol (M.I.B.C.) - 10% blend (for comparison) (ii) Sunflower oil with M.I.B.C. 10% blend (iii) Sunflower Oil Alone The reagent flow was adjusted so that produced a foam concentrate with 9 to 12% ash.

The results of three test groups, each with three flotation runs are given below: Run reagent reagent additive foam concentrate No. kg / ton% ~~~~~~ ~~~~~~~~~~~~~% Yield% ash 1 sunflower oil 0.32 54.5 9.5 2 + M.I.B.C 0.40 56.6 10.5 3 0.48 59.0 11.5 4 Sunflower oil 0.62 37.0 9.5 5 0.72 47.2 10.5 6 0.86 61.5 11.5 7 Kerosene + 0.39 44.0 9.5 8 M.I.B.C. 0.46 47.0 10.5 9 (control) 0.54 52.0 11.5 The results show a better yield using of sunflower oil plus M.I.B.C. than when using kerosene plus M.i.B.C. at a higher addition of sunflower oil alone, the yield is greater than with kerosene plus M.I.B.C. with the same ash content.

Claims (4)

Process for the flotation of a mineral Claims 1. Process for the flotation of a mineral, in that it is not indicated that the flotation of the mineral is carried out using at least one oil of vegetable origin. 2. The method according to claim 1, characterized in that g e k e n n -z e i c h n e t that the oil is sunflower oil. 3. The method according to claim 1 or 2, characterized in that g e -k e n n z e i c Don't say the mineral is broken coal. 4. The method according to any one of claims 1 to 3, characterized g e k e n n shows that the mineral is broken and slurried with water, that-that Vegetable oil and optionally a foaming agent are added, and that agitation he follows.