DD159874A1 - PROCESS FOR PRODUCING ORGANIC GRINDING AGENTS FOR CEMENT PRODUCTION - Google Patents

Abstract

The additives obtained by the process for producing organic grinding aids for cement production cause an intensification of the milling process of cement raw materials, are highly effective, meet the economic requirements, can be precisely metered and do not affect the strength of the concretes. According to the invention, a residue obtained from the acidic hydrogenation of acetaldol, subsequent distillation, posthydrogenation of the mixture boiling over 100 degrees and stripping of the low boilers is mixed with a residue in the ratio 4: 1 to 1: 4 by neutral hydrogenation of acetaldol and after abortion of all distillable fractions is obtained. The addition of water up to a content of 20% in the grinding aid facilitates its meterability in the milling process by lowering the viscosity.

Description

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Title of the invention

Process for producing organic grinding aids for cement production.

field of use the invention

The invention relates to a process for the preparation of organic additives for the Zementmahlprozeß "These additives cause at aer grinding cement raw materials, that a higher degree of fineness of the cements, a reduction of the electric energy expenditure and improve the quality of concrete can be achieved.

Characteristic of the known technical solutions It is known to use aids, usually organic substances, for intensifying the cement grinding process. DD-PS 63733 and 79252 describes the addition of polyols, in particular octanediol, to cement clinker during the milling process. These additives are by-products or residues from the ethylene glycol, glycol ether or propylene glycol synthesis or the synthesis of butylene glycol. The accumulation of these additives is bound to these syntheses. Increasing the production of these grinding aids required by the cement industry in larger quantities is only possible to a limited extent · _:

The grinding aids proposed by DD-PS 103 227, such as amines, alcohols and carboxylic acids, can not be used on a large scale for commercial reasons.

Object of the invention

The aim of the invention is to provide for the cement grinding process a highly effective grinding which meets the economic requirements.

to produce an additive which ensures an intensification of the processing process and does not have any adverse side effects in the concretes, eg "does not impair the strength of the concretes." An increase in the volume of grinding aids is to be made possible by the invention.

Explanation of the essence of the invention. ,

The invention has for its object to develop a process for the production of organic grinding aids for cement production "that meets the above requirements"

The object is achieved in that a obtained by acidic hydrogenation of acetaldol and subsequent distillation over 10O ⁰ C boiling mixture again hydrogenated, the low boilers are stripped and the over 200 C boiling bottom product is mixed with a residue consisting of a neutral hydrogenation of the Acetalaols with subsequent abortion of all distillates remains »

The grinding aid according to the invention produced contains octanediol, and hexanetriol both lower and higher PoIyole "From aer practice of Zementklinkervermahlung However, it is known that lower polyols, such .. B _e butane-1,3-diol, and also higher polyols having a carbon number of about 10 are unsuitable «

It is thus surprising for the skilled worker that the grinding aid according to the invention in the combination of suitable and unsuitable ingredients for the Mahlpro ~ zeß effects a use effect that fully corresponds to that of the known most effective grinding aids.

With the grinding aid according to the invention are ^p roi duktionssteigerungen during milling by shortening the meal reaches at least 10%, the degree of fineness of the cement produced significantly increased and the quality of certain types of cement for further processing positively influenced.

To achieve a good metering of the grinding aid, the viscosity is reduced by the addition of water to the extent required. The water content of the finished grinding aid comes to lie between 1.0 and 20%.

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The grinding aid is precisely metered due to its low viscosity, does not cause corrosion on the equipment and does not affect the strength of the concretes.

The proportion of grinding aids, based on the Acetaldo 1 _{# used,} can be increased by increasing the pH and the temperatures at the hydrogenation stages. «

embodiment

The invention will be explained in more detail below with reference to a drawing by an embodiment.

Acetaldol (1) obtained by known methods by alkaline condensation of acetaldehyde is acidified with about 0.5 % acetic acid (2) and hydrogenated at 120 to 160 ° C and a pressure of 5 Mf on a palladium catalyst (5). To isolate the butyraldehyde formed and for the recovery of unreacted acetaldehyde, the hydrogenation product (6) is distilled to a temperature of 100 ⁰ C (7), the remaining distillation residue (8) is subjected to 80 to 180 ° C and a pressure of 25 MPa a complete hydrogenation (9) on a nickel-copper-chromium catalyst. From the obtained Reaktionsprpdukt the low boilers (11) are stripped (19), after which the about 200 ⁰ C boiling bottom residue (12) which forms a component of the grinding aid. The second component of the grinding aid is also prepared from acetaldol (1), but with the difference that this is subjected in the neutral state (3) immediately complete hydrogenation (13) on a nickel-copper-chromium catalyst _e From the hydrogenation product ( 14) werder all separated up to a boiling point of about 180 ⁰ C with 1.5 KPa overstilling materials (15).

The no longer distillable residue (16) of higher polyols forms the 2, component of the grinding aid · Both components! are in the ratio of 4: 1 to 1: 4, preferably in the ratio 1: 1, mixed, wherein to reduce the viscosity of water (17) to a content of 20 %, preferably 12 to 18%, is added.

Claims (2)

Erfindungsansprach 1. A process for the preparation of organic Mahlhilfsmittel for Zementprodui'on by acidic hydrogenation of Aoetaldol, followed by distillation and rehydrogenation of over 100 ° boiling mixture, stripping the low boilers, and neutral hydrogenation of Aoetaldols with subsequent abortion of all distillable fractions, characterized in that 'The residue resulting from the stripper with the residue from the abortion of all distillate portions in a ratio of 4: 1 to 1 ί 4-, preferably 1 j 1, is mixed and the mixture water to a content of 20%> preferably 12 to 18 %, is added. 2. The method according to item 1, characterized in that the grinding aid in addition to octanediol and hexanetriol both lower and higher polyols. For this 1 page drawings