DE1084113B - Process for the fine grinding of a grist with the addition of color bodies - Google Patents

Description

The invention relates to a method for the fine grinding of a material to be ground with the addition of an or several color bodies, e.g. B. a metal oxide. At the same time fine grinding of such substances, z. B. from Clay, quartz and colored ore, as is common in the ceramic industry, have been used so far, particularly at the use of mill systems that work with air separation, prematurely the more easily grindable substances brought to the desired fineness. This resulted in an over-grinding of these substances, what is sometimes undesirable, while the more difficult to grind substances with less great fineness discharged from the mill and fed back to it in the semolina return. Albeit through this one steady cycle of difficult-to-grind substances gradually a certain state of equilibrium occurred, so it has been found in many years of practice that the more difficult-to-grind substances are in the mill accumulated more and more, so that, especially shortly before stopping the mill, z. B. at closing time, essentially the harder substances are discharged and thus the mixing ratio of the ground product has been significantly changed. This resulted, for example, in the addition of coloring agents Oxides, such as metal frits, chrome ore or manganese ore, for a stronger color enrichment in the last part of the grist. Unless this part was discarded, the color enrichment gave one unevenly colored end product and thus rejects.

It is now already known a ball mill in which the more difficult to grind material, such. B. cement clinker, at the front end of the grinding drum and the more easily grindable material, e.g. B. plaster, with the help of a central Screw inside the grinding drum at a point on the grinding path that is closer to the rear end is introduced, which corresponds to the grindability of the goods. This type of feeding a lighter But there is little that can be grinded for grinding pigments together with another grist suitable for difficult grindability. Namely, when passed from one color body to another is to be, need not only those parts of the grinding drum or the compartment with this device the grinding drum, which are located behind the feed point of the color body, but also to the for the most part those that are in front of the feed point are cleared and cleaned, there already minor impurities in the first color body can render the second mill product unusable.

The object of the invention is to overcome this disadvantage in the fine grinding of a material to be ground along with one or more color bodies to avoid. The object is achieved in that procedure

for fine grinding of a grist
with the addition of color bodies

Applicant:

Klöckner-Humboldt-Deutz

Corporation,
Cologne-Deutz, Mülheimer Str. 149/155

Dr.-Ing. Georg Baron, Cologne,
has been named as the inventor

a vibrating mill with two or more connected in series Grinding tubes are used to which the color bodies are fed at the transition from one grinding tube to another. In this procedure When changing the color body, only the grinding tubes behind the feed point of the color body need to be cleaned. In addition, will In the process, a grist with a very uniform grain distribution is achieved, since the color bodies have a shorter grinding path than the more difficult-to-grind constituents of the grist and substances Easier grindability to be fed to the milling tubes behind the feed point of the color bodies can and thus in turn go through a shorter grinding path than the color bodies.

When fine grinding particularly color-sensitive masses, for example ceramic masses, with the addition of color bodies, it can still happen that the masses are certain when fired Have color differences. In such cases it is according to a further embodiment of the invention expedient to pre-grind the color body (s) separately in a wet mill and demolish it to add the rest of the regrind.

The drawing shows schematically an embodiment of the device with which the invention can be realized, namely the drawing shows a vibrating mill with two grinding tubes 1 and 2. The grinding tube 1 has a filler neck 3 at the left end and is over at the right end a transfer tube 4 is connected to the grinding tube 2. This also has a filler neck 5 and on a discharge nozzle 6 on the left end. At the transfer point opens into the grinding tube 2

009 547/222

Line 7, which is connected to the outlet of a wet mill 8, for example a ball mill.

Colored ceramic masses require an addition of 1 to 5% of coloring metal oxides, z. B. of cobalt oxide, chrome ore or similar metal oxides. These additives at the same time as the ceramic To grind mass has so far failed because then the end product as a result of the small portion The additives do not have a uniform, homogeneous color, but rather colored bodies appearing in individual dots contained. As a result, it has hitherto been customary to predominantly stretch the color bodies and the stretched ones Add color bodies to the mill in the appropriately crushed state.

According to the invention, quartz and feldspar are now introduced into the grinding tube 1 through the filler neck 3. The color bodies are pre-ground in the wet mill 8. You will then put the quartz-feldspar mixture on it at its transition from the grinding tube 1 into the grinding tube 2 in the form of a turbidity through the Line 7 added. The ceramic mass is finally through the filler neck 5 of the grinding drum 2 supplied. The grinding process takes place in this grinding tube with simultaneous homogenization of the grist ended. In the method according to the invention, a milled product results very much uniform color and grain distribution. Also the cleaning of the grinding tubes or the wet mill at The transition from one grinding media to another is relatively easy to carry out.

Claims (2)

Patent claims: 1. A method for the fine grinding of a material to be ground with the addition of one or more color bodies, e.g. B. of a metal oxide, characterized by the use of a vibratory mill with two or more series-connected grinding tubes, which the color bodies at the transition from a grinding tube in another to be fed. 2. The method according to claim 1, characterized in that that the color bodies are pre-ground in a wet mill. Considered publications:
German Patent No. 936 003;
U.S. Patent No. 1,825,333;
"Glückauf" magazine, 1955, p. 893, fig. 1. 1 sheet of drawings © 009 5 * 7/222 6.60