DE1667065B2 - Grinding aid - Google Patents

Description

The present invention relates to the use of an additive to improve the Properties of minerals.

When processing pretreated or untreated minerals, these usually become too Grind relatively small particles, which should be done as quickly as possible. Here are often Grinding aids used to increase the grinding speed or the fineness of the particles to increase given operating speed without dad the ground product is adversely affected.

The breaking up of the particles when grinding minerals creates new, high-energy surfaces, whose surface forces remain even after the grinding process and the Material or a poor pourability result. This leads to the fact that ground minerals through the z. B. occurring during transport vibration are compressed in such a way that they are often semi-solid and themselves do not allow to be poured out, unless you have to use considerable mechanical means to break up the compact mass Uses forces

This agglomeration or adhesion of individual particles is referred to as “solid baking” (pack set) and determined by the Festback index; this is a relative value which numerically indicates how far a particulate matter is ready to flow freely after a certain storage time or after transportation. The ratio of the caking index of untreated material to that of treated material is referred to as the "solid baking ratio" and is used to compare two different samples of ground Minerals.

This hard baking index is determined as follows: 100 g Mineral are placed in a 250 ml Erlenmeyer flask vibrated on a vibrating plate for 15 seconds and then inserted horizontally in a chuck. Of the The flask is then rotated about 100 ml per minute by 180 ° around its axis until it is at the bottom of the flask Fixed material collapses The number of rotations through 180 °, which are necessary until the collapse of the Materials are required, result in the fixed baking index. ) e bigger so the one to break open the festgebakkenen Material required energy, the higher

is the solid baking index.

It has now been found that amine salts of aryl hydroxy compounds e.g. B, phenol as excellent grinding aids and as caking inhibitors for Minerals act without z. B. with cement, the strength of the concrete is impaired.

Accordingly, the invention relates to a mixture which consists of a mineral and one with this Mineral intimately mixed amine salt of an arylhydroxy compound consists of one or several arylhydroxy compounds mixed with one or more amines The starting materials can be pure chemicals or raw materials with impurities. The method of manufacture these additives are known. Preferably, equimolar parts are amine and arylhydroxy compounds used

The arylhydroxy compound preferably consists of a phenyl or naphthyl radical, which by is substituted by a hydroxyl radical and which is otherwise unsubstituted or by one or more Nitro groups, halogen groups, preferably through chlorine, alkyl radicals, preferably with 1 to 5 carbon atoms and in particular methyl radicals, through aryl radicals, Amino or alkoxy groups with preferably 1 to 5 carbon atoms is substituted

Preferably the amine is a compound of the following general formula:

NO,

in which Ri is a hydrogen atom or a substituted one or unsubstituted alkyl radical, such as hydroxyalkyl or aryl ζ. B. Alkaryl radical and R2 is a hydrogen atom or a substituted or unsubstituted Aikylrest z. B. a hydroxyalkyl radical and Rj a hydrogen atom, a hydroxyl radical or a substituted or unsubstituted alkyl radical, e.g. B. a hydroxyalkyl or aryl radical or a compound of the following

r. Formula mean:

.ο in which

R ⁴ NR ⁵

i I

R ⁴ N

a substituted or unsubstituted pyrrolidinyl, pyrrolidyl, pyrrolyl, morpholinyl, piperidinyl or piperazinyl radical and R ⁵ denotes a hydrogen atom or an alkyl or hydroxyalkyl radical; or Y- (R ^) _n .

mi in which Y is a pyridyl, pyrimidinyl or pyridizinyl radical and Rf is a halogen atom or an alkyl or hydroxyl radical and η has the value from Ö to 5 .

Suitable amines are, for example, ammonia,

tr, ethylamine, diethanolamine, monoethanolamine, triethylamine, Triethanolamine, aniline, p-toluidine, m-phenylenediamine, Dimethylaniline, Diphenylamine ^ Aö-Tribromaniline, N-phenylhydroxylamine, / J-phenäthylemine, morpho-

lin, pyridine, piperidine, pyrrole, pirroline, pyrrolidine, Pyridazine, pyrimidine, N-methylmorpholine, 4- (2-aminoethoxy) ethylmorpholine, Dimethylpyridine, dimethylethylpyrrole and piperazine.

Naturally occurring inorganic minerals such as phosphate rock are sometimes used as minerals processed minerals such as concentrated iron ore and mixtures of minerals such as cement, clinker or ceramic materials treated in this way. For example, such grinding aids can be used Treat beryllium oxide, limestone, gypsum, clay and bauxite. Such grinding aids are particularly valuable in cement and especially portland cement, in which they even increase the strength of the lead set concrete. Portland cement is one of the hydraulic cements, which is essentially made up of two calcium silicates and a smaller amount of calcium aluminate. Such cements are produced by an intimate mixture of a finely divided limestone together with clayey The material is processed into a uv clinker brick and then this ground together with about 2% plaster of paris or with another calcium sulfate to achieve the desired setting properties of the finished cement. The amine salts are preferably added to the clinker, in order to increase the grinding efficiency and subsequent setting of the finished cement avoid; however, they can also be added at a later point in time. Improving the Properties is independent of the time of addition, and there will be an increase in particular Strength achieved in hardened concrete.

The grinding aids according to the invention are either set dry or liquid. Because of Ease of use, aqueous solutions can be used that are precisely proportioned to the production area can be. Less soluble grinding aids can be mixed with an appropriate wetting agent, e.g. B. Sodium dodecylbenzenesulfonate. The grinding aid can be added to the mineral prior to grinding can be added or can be added to the grinder at the same time as the material.

If only the caking is to be reduced or a better flowability is to be achieved - e.g. B. at Conveyance or pneumatic transport - so the grinding aid / u can be any other Time to be added during work-up.

The amount of the grinding aid can vary widely, but it is preferably 0.001 up to I and in particular 0.004 to 0.4% solids, based on the weight of the Mincral solids, added. There is no upper limit on the amount of grinding aid added, but usually will only enough added to achieve the desired flowability and surface reach.

The grinding aids according to the invention are preferably used alone, but can also be used with one or several other grinding aids or other additives are processed together.

In the following, the invention is intended to anhana of Examples are explained in more detail.

Example I.

The following table shows the effectiveness of the triethanolamine phenoxide used as a grinding aid reproduced, which is made by mixing equimolar parts of triethanolamine and phenol became. The measurement results were obtained with a Portland cement type 1, which is used in the Laboratoriumsiahlku- _> i) gel mill ground at 99 ° C and 3403 revolutions became.

Amount of addition Surface after increase in% (FcslstolTc je HIaine crir / g opposite to Solids) Blind proc 0.01 ΛΙ14 4.21 0.02 3128 5.20 0.03 3121 4.45 0.04 3134 5.41 0.06 3134 4.89 0.08 3184 7.09

Example 2

A grinding aid was prepared by mixing 34 parts by weight of a mixture of phenol and cresol in the ratio of 50:50 with 65.9 parts by weight of a mixture of morpholine and triethanolamine in the ratio of 50:50. The milling efficiency was determined with Portland cement Type I, which was ground in a Laboratoriumstahlkugfiimühle at 110 ⁰ C and 4941 rpm. At a content of 0.12% by weight, based on the cement weight, there was an increase in the values for the surface according to BI ai η c of 6.75% compared to the blank sample.

The additives of the invention are also used with good results in grinding others Minerals other than cement used, for example, as grinding aids for phosphorus stcin and iron ore.

Claims (4)

Patent claims: 1. Use of an amine salt of an arylhydroxy compound as an additive to minerals, in particular cement and cement-forming mixtures. 2. The use of an additive according to claim 1 in an amount of 0.001 to 1 wt .-% and preferably 0.004 to 0.04 weight percent based on the weight of the mineral. 3. Use according to claim 1 or 2, characterized in that a triethanolamine phenoxide or a reaction product of morpholine and triethanolamine with phenol is used. 4. Mineral mixture containing a derivative of an arylhydroxy compound, characterized in that that as a derivative of an arylhydroxy compound and as a caking inhibitor from an amine and the arylhydroxy compound by reaction on the Hydroxyl group formed salt is used.