DE1194342B - Process for the electrostatic processing of potash salts - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. α .:

B 03 c

German class: 1 b - 6

Number: 1194 342

File number: K 42347 VI a / l b

Filing date: December 8, 1960

Opening day: June 10, 1965

It is already known that most crude potassium salts are found in the electrostatic treatment Use chemical conditioning agents to achieve excellent separation results. Besides However, there are a few crude salt deposits that contain high levels of clay or clay-like minerals or by certain other substances present in particularly fine form, such as fine gravel, Koenenite, among others, are contaminated. In the electrostatic processing of crude salts, the aforementioned Have impurities, while using a single type of separator, for example of the free-fall separator, also achieved satisfactory separation results.

It has now been shown, surprisingly, that by using a combination of free fall and roll cutters also have such, particularly difficult to process potash crude salts with still significantly Better separation results can be prepared than using the same conditioning agent is possible with the help of only one of the two types of separator. The mode of action of the invention The procedure is best demonstrated using the following three examples, with the Conditioning was done by known means. The values obtained are for the sake of clarity summarized in a table.

In fact, columns d of experiments 1, 3 and 5 show the percentages of the pre-concentrate after the ground and conditioned crude salt has passed through a free-fall separator once, and columns e show the percentages K ₂ O of the so-called

Process for electrostatic processing
of potash salts

Applicant:

Potash Research Institute G. mb H.,
Hanover, Georgstr. 29

Named as inventor:

Dr.-Ing. Hans Autenrieth, Hanover-Kirchrode;

Dr. rer. nat. Gerd Peuschel,

Benthe near Hanover;

Dr. rer. nat. Günter Weichart,

Hanover-Döhren

Post-concentrate, which is obtained during the second passage of the salt through the free-fall separator. Experiments 2 and 4, which work according to the method according to the invention, show the percent K ₂ O of the pre-concentrate in columns d after a single pass through a free-fall _{separator and then in columns e the percent K 2} O of the post-concentrate after a further pass by a roller cutter. In experiment 6, only the order of the separators is reversed, ie first roller separator, then free-fall separator.

Example I.
Potash crude salt with 13.2% K ₂ O and a high proportion of fine gravel (grain size 0.1 mm)

a split
b C. d e Separator type Fine gravel content
(0.1 mm grain size)
% Residue
° / o K ₂ O before
concentrate
% K ₂ O To
concentrate
7oK ₂ 0 Experiment 1 ■ Pre-concentration:
Freefall separator
Post-concentration:
Freefall separator 30.4 2.1 41.2 51.9 Experiment 2 ■ Pre-concentration:
Freefall separator
Post-concentration:
Roller cutter j 30.4 2.1 41.2 59.7

509 579/64

3 4

Example II Crude potash salt with 12.0% K ₂ O and a high proportion of koenenite

split

Separator type

Coenenite
in raw salt

Residue
° / o K ₂ O

Pre-concentrate
¹ VoK ₂ O

Post concentrate

% K ₂ O

Attempt 3

Attempt 4

Pre-concentration:
Freefall separator

Post-concentration:
Freefall separator

Pre-concentration:
Freefall separator

2.5

2.5

2.2

2.2

Post-concentration:
Roll cutters

B e i s ρ i e 1 III

Potash crude salt with 18% K ₂ O and high clay content

36.1

36.1

52.2

57.7

a split
b C. d e Separator type Clay content in
Raw salt
% Residue
% K ₂ O before
concentrate
¹ YoK ₂ O To
concentrate
° / o K ₂ O Experiment 5 Pre-concentration:
Freefall separator
Post-concentration:
Freefall separator 10.01 2.2 36.4 47.2 Experiment 6 ■ Pre-concentration:
Roll cutters
Post-concentration:
Freefall separator 10.01 2.5 36.3 54.2

The evaluation of the numerical results of the three examples gives the following picture:

According to Example I, the post-concentrate of experiment 2 (free-fall separator - roller separator) according to the invention shows a K ₂ O content that is 7.8% higher than the post-concentrate according to comparative experiment 1 (free-fall separator - free-fall separator).

According to Example II, the K ₂ O content of experiment 4 according to the invention (free-fall separator — roller separator) is 5.5% K ₂ O higher than in comparative experiment 3 (free-fall separator - free-fall separator).

According to Example III, the K ₂ O content of the post-concentrate of Experiment 6 according to the invention (roller separator - free-fall separator) is 7% K ₂ O higher than in comparative experiment 5 (free-fall separator - free-fall separator).

The progress of the separator arrangement according to the invention is therefore surprisingly great.

To evaluate the method according to the invention on the basis of the results contained in the tables above, it should be noted that when processing high-clay potash crude salts with the free-fall separator in two passes (see Example III, Experiment 5), it is in some cases impossible to add subsequent concentrates achieve whose K ₂ O content is significantly above 50%.

On the other hand, when using the method according to the invention, by splitting the post-concentrate according to experiment 6 into two parts, a final concentrate can be achieved, two-thirds of which consists of a product with over 60% K ₂ O (> 94% KCl), while one-third of the post-concentrate contains 40% K ₂ O is obtained. Both products are trademarks and can be sold directly.

It is precisely the proportion of a high-percentage end concentrate with 60% K ₂ O that is of great economic interest in the processing of crude potash salts, as the demand for high-percentage fertilizer salts is constantly increasing.

Claims (2)

Patent claims: 1. Process for the electrostatic processing of a high content of clay or clay-like Potash crude salts containing minerals, characterized in that the pre-concentration in a single or multi-stage roller separator and the post-concentration in a single or multi-stage free-fall separator he follows. 2. Process for the electrostatic processing of a high content of fine-grain kieserite, Koenenite or the like containing crude potash salts, characterized in that the preconcentration in a single or multi-stage freefall separator and the post-concentration in a single or multi-stage roller cutter takes place. 509 579/64 6.65 © Bundesdruckerei Berlin