CS270602B1 - Method for concrete mixture without gypsum preparation - Google Patents

Abstract

The invention provides a gypsum-free cement mixture and a process for the production thereof. The mixture can be used in building and construction particularly if it is desired to have good processability with simultaneously high initial (early) strengths. The mixture contains a Portland cement clinker having a specific surface area of 220-700 m<2>/kg, a milling additive, an alkaline compound selected from the group consisting of carbonate, hydrogen carbonate or silicate and a sulphonated polyelectrolyte selected from the group consisting of lignosulphonate, sulphonated polyphenolate or sulphonated lignin. The invention is essentially that the mixture contains 20-55% by weight of make-up water with 0.01-0.6% by weight of triethylamine, 0-2.2% by weight of the alkaline compound and 0-2.2% by weight of the sulphonated polyelectrolyte, all percentages being based on the mass of the cement clinker. The process for producing the mixture essentially comprises mixing a Portland cement clinker having a specific surface area of 220-700 m<2>/kg, a milling additive, an alkaline compound selected from the group consisting of carbonate, hydrogen carbonate or silicate and a sulphonated polyelectrolyte selected from the group consisting of lignosulphonate, sulphonated polyphenolate or sulphonated lignin and then adding to this mixture 20-55% by weight of make-up water together with 0.01-0.6% by weight of triethylamine dissolved therein. The make-up water can also contain up to 2.2% by weight of an alkaline compound and up to 2.2 ... Original abstract incomplete.

Description

The present invention relates to a process for the preparation of a gypsum-free cement composition having an extended setting and a high initial strength. *;

The prior art gypsum-free cements (BS), which are a new type of inorganic hydraulic binder, are based on ground Portland cement clinker with a specific surface area of 220 to 700 m / kg, using a synergistically acting mixture of an alkaline compound instead of gypsum. ,. e.g., soda, potash, NaHCO 3, and a sulfonated polyelectrolyte, eg, lignin sulfonate, sulfonated lignin or sulfonated. .pclyphenolate. The composition of these binders and their properties have been described in U.S. Pat. No. 3,689,294, U.S. Pat. No. 3,959,0-4, U.S. Pat. No. 4,168,385, U.S. Pat. No. 4,551,176 and U.S. Pat. A0 198 053; 203 212 and 225 066. The binders described above also contain grinding aids, such as ethylene glycol, dodecylbenzenesulfonic acid triethanolamide or triethanolamine (hereinafter TEA). The use of TEA as a grinding additive has long been known. TEA is proven to be a highly effective grinding additive for Portland cements, coportland cement slag and slag. It is used alone in TEA or in admixture with other substances, as is evident from numerous journal literature: Scheibe W., Dallmann W. 1, 11-17 (1971); 7, 243-245 (1975); 10, 413-418 (1979); 2, 69-74 (1974), Opoczky L .: Epitoanyag. 5, 188-193 (1969), and Scheibe W., Dombrowe H., Mezhunarodnyi Congress after Super-active Hangings, Moscow 1978, pp. 521-529. Also many patents disclose details of the use of TEA as a grinding additive: Japan 8075748, 8075747, USSR 567, 788, JAR 7403631, MS. АО No. 253 499, MS. A0 No. 257385. TEA also affects the setting point, processability and strength development of Portland cements. These findings are given, for example, in: Dusumdarov J., Kontsepolskij I., S .: Uzbeckij Khimicheskij Journal, vol. 18, 55-57 (1974), Tenovtasse N., Czamarska D .: Cement-Wapno-Gips vol. 29 , 96-102 (1974) and Silicates Industry vol. 38, 233-238 (1973), Lieber W., Richartz W., Zement-Kalk-Gips vol. 25, 403-409 (1972), Tashiba L., Katami H .: Semento Gijutsu Nenpo vol. 33, 87-90 (1979); Ramachandran VL: Cement Conorette Research vol. 6, 623-631 (1976); and Belgium 866916 et al. АО 222,365.

A disadvantage of the prior art solutions of cementitious compositions using combinations of the above additives is the particularly slow increase in strength within eight to fifteen hours of setting. A further disadvantage is the relatively short setting time and the setting time instability depending on the time of mixing the binder with water or the storage time of the additive solutions; i.e., the alkali component and especially the sulfonated polyphenolate.

The disadvantage of the present invention is to eliminate the gypsum-free cementitious composition of the present invention by providing a grinding additive, such as ethylene glycol or dodecylbenzenesulfonic acid triethanolamide, an alkaline compound, such as a Portland cement clinker having a specific surface area of 220 to 700 m / kg. carbonate, bicarbonate or silicate, and a sulfonated polyelectrolyte, such as lignin sulfonate, sulfonated plyphenolate or sulfonated lignin, are added 0.01 to 0.3% by weight, triethanolamine dissolved in 20 to 55% by weight, mixing water, wherein the weight percentages are based on clinker weight.

Addition of TEA up to the mixing water and subsequent mixing with the prepared mixture can increase the initial strength of the BS cements - in the order of hours after solidification - especially when using the combination of lignin sulphonate + alkaline compound. The properties of the solutions of sulfonated polyphenolates in admixture with alkali carbonate are stabilized and the onset of solidification is prolonged. The advantage is also improved workability of mixtures of BS cements while reducing the viscosity of cement slurries.

A number of gypsum-free cements have been prepared for the experiments, the characteristics of which are given in Table 1. Examples are provided in a specific application, but are not intended to limit the invention in any way.

CS 270 602 80

Table 1

Process for preparing B5 cement, surface area; Marking of the grinding set Grinding sets______________ _ _ * vibrating mill 20 1, clinker Maloměřice,

620 m ² / kg, 0.05 * triethanolamine ball mill 50 l, clinker Hranice,

420 m / kg, without grinding agents ball mill 50 1, clinker Hranice ·

420 n ^ / kg, 0,05% triethanolamine vibrating mill 20 l, clinker Lochkov,

510 m ² / kg, 0.1% ethylene glycol vibratory mill, clinker Lochkov

630 m ² / kg, 0.03% dodecylbenzenesulfonic acid triethanolamide ball mill 30 l, clinker K. Dvůr

240 m ² / kg, 0.025% dodecylbenzenesulfonic acid triethanolamide ball mill 150 l, clinker containing% alite, 9% belite, 8% C ^ A 580m / kg, and 9 4 C ^ A _x Fy without grinding ball mill 150 l , clinker containing

4 alite, 17% belite, 2% С, A and 15%

Wy> 43 ° ^m / kg, without grinding additive ball mill 150 l, clinker containing% alite, 14% belite, 8% C, A and 6 * ^ 4 ^ x ^ y * ^m ^ 9 without ^m ^ ^ec ^ additive vibrating mill 201, clinker Štramberk

0.1 4 ethylene glycol, 420 m / kg vibrating mill 201, clinker Štramberk

0.05 4 triethanolamine, 460 m / kg

Malomerice 620 (0.05% TEA)

Border 420 (pure)

Border 420 (0.05% TEA)

Lochkov 510 (0.1 4 ETG)

Lochkov 630 (0.03% TEOB)

K. Dvur 240 (0,025 \ TEOB)

SK 580 (pure)

DG 430 (pure)

SL 470 (pure)

Stramberk 420 (0.1% ETG)

Stramberk 460 (0.05 4 TEA)

Example 1

BS cement Štramberk 460 (0,05 V TEA) and Štramberk 420 (0,1 ETG) were prepared

I a slurry of water coefficient w * 0.25 of free-flowing consistency with the additions of 1.3% Na ₂ SO ₃ and 0.9% oxidized sodium lignin sulphonate (clinker weight). The BS cement slurry of Štramberk 420 (0.1% ETG) reached the following strengths: 2 MPa after 2 hours from solidification, 2.2 after 5 hours after solidification, 4.5 MPa after 24 hours, 95 MPa after 7 days. The BS cement slurry of Štramberk 460 (0.05% TEA) reached the following strengths: 1.7 MPa after 2 hours after setting, 2 MPa after 6 hours after setting, 2.8 MPa after 24 hours after setting, 8.5 MPa after 7 days. By using TEA as an additive to the mixing water, a higher effect was achieved in the development of strengths: a slurry prepared from BS cement Štramberk 420 (0.1% ETG) and 0.05% by weight clinker and the same ingredients listed above: 2 hours after solidification 2 5 MPa, after 4 hours 3 MPa, after 24 hours 40 MPa and after 7 days 80 MPa. Using 0.1% TEA in mixing water, the strengths increased to 50 MPa after 24 hours and to 95 MPa after 7 days. Using the method according to the invention, the strengths have increased up to 20 times after 24 hours.

CS 270 602 B1

Example 2.

A free-flowing slurry sw = 0.25 was prepared from BS cement Lochkov 510 (0.1% ETG) with the addition of 1% by weight of clinker Na ₂ CO 4 and 0.64% by weight of clinker sulfonated sodium ferric polyphenolate. When the brewing water with both additives was used immediately to prepare the slurry, the setting time was 70 minutes. If the brewing water with the ingredients was left 60 minutes before the slurry was prepared, then the onset of solidification was shortened to 35 minutes. When using the process according to the invention, where 0.05% by weight of triethanolamine cement was added to the brewing water, the start point of solidification was immediately 90 minutes after mixing the mixed water with the additives. 85 minutes. The addition of TEA to the mixing water acted as a stabilizing agent.

Example 3

A slurry w = 0.25 of free-flowing consistency was prepared from BS cement Malomerice 620 (0.05% TEA) with the addition of 0.4% sulfonated ferric polyphenolate and 1% Na ₂ CO 3. The mixing water with the ingredients was used immediately to prepare the slurry and after 30 seconds of slurry stirring, the start of solidification was 55 minutes. Under the same procedure and stirring the slurry for 3.5 minutes with a rapid mixer, the onset of solidification was reduced to 40 minutes. After adding 0.05% by weight of the triethanolamine clinker to the mixing water, the onset of slurry solidification was independent of stirring time and was 55 minutes.

Example 4 ’

BS cement Malomerice 620 (0.05% TEA) prepared a slurry w = 0.27 with the addition of% soda and 0.64% sulfonated sodium ferric polyphenolate (used as a 36.6% solution). The slurry was stirred for 1 minute and had a setting time of 100 minutes. The same slurry after preparation mixed with a rapid mixer for 3 minutes had an onset of solidification as early as 50 minutes. For further experiments, a sulfonated polyphenolate solution was prepared to which 0.05 4 TEA (calculated on cement weight) was added. This solution was used to prepare the slurry immediately - the onset of slurry solidification was after 80 minutes; then, after 48 hours of mating, the start of solidification was 75 minutes and after storage of the solution for 4 months the start of solidification was practically the same - namely 80 minutes.

Example 5 '

Slurries were prepared from BS cement Lochkov 630 (0.03% TEDB) with the addition of 0.4% sulfonated ferric polyphenolate and 1% Na ₂ CO 4. The properties of the slurries are given in the following table:

without addition of TEA to lock. water into the chateau water added 0.05% TEA 1

w the beginning of solidification viscosity the beginning of solidification viscosity 0.22 55 min. 2.02 Pas 80 min. 1.9 Pas 0.24 60 min. 1.49 Pas 105 min. 1,3 Pas 0.25 70 min. 1,2 Pas 160 min. 0.92 Pas

Addition of TEA to the mixing water can reduce the viscosity of the slurry and prolong the onset of solidification.

Example 6

From BS cement Lochkov 630 (0.03% TEOB) a slurry w = 0.20 of liquid character with a viscosity of 3.1 Pas was prepared with 1% Na ₂ CO 3, 0.64 4 sulfonated sodium ferric polyphenolate and added to the mixing water. 0.07% TEA (all cement weight) added. The start of solidification of the slurry was after 120 minutes and the slurry reached 2 MPa after 2 hours of solidification and 79 MPa after 24 hours.

CS 270 602 B1

Example 7

BS Cement Bound 420 (0.05 4 TEA) and Bound 4.20 (pure) were prepared at w = 0.25 slurry with the addition of 1% Na 2 CO 3 and 0.4% sulfonated ferric polyphenolate. BS cement slurries Hranice 420 (pure) had a free-flowing character and a setting time of 90 minutes. After adding 0.05% by weight of TEA cement to the mixing water, the onset of solidification was extended to 140 minutes. BS cement slurry boundary 420 (0.05% TEA), ie from the same clinker, but TEA was added as a grinding additive, had a pasty (plastic) character and an onset of solidification of only 100 minutes.

Example 8

A slurry w = 0.25 of liquid nature was prepared from BS cement Lochkov 630 (0.03 4 TEDB) with the addition of 1.5% sodium oxidized lignin sulphonate. This slurry had an onset of solidification after 60 minutes, while the same procedure and after the addition of 0.05% TEA to the mixing water extended the onset of solidification to 90 minutes.

Example 9

Mortar (1: 3.3 fraction of sand) was prepared from BS cement Malomerice 620 (0.05% TEA) at w = 0.31. 1 4 Na ₂ CO 4 and 0.64% sulfonated sodium ferric polyphenolate were added to the mixing water. In preparation, the mortar was mixed for 1.5 minutes and had an onset of solidification after 70-80 minutes. When the mixing time was extended to 5 minutes, the start of solidification was reduced to 45 - 50 minutes. In the second phase of the experiment, a mortar with the same ingredients was prepared, but 0.05 4 TEA was added to the mixing water and the mixing water with all ingredients was allowed to stand for 2 hours before mortar preparation. The onset of solidification was independent of the mixing time and was 60-70 minutes.

Example 10.

Slurries w = 0.24 were prepared from BS cement SK 580 (pure) with the addition of 0.8 4 Na ₂ CO 2 and 1.2% monosaccharide-free sodium ligninsulfonate. The onset of slurry solidification was after 25 minutes. The slurry reached compressive strength: 2 hours after solidification of 2.5 MPa, 6 hours after solidification of 6.3 MPa, 24 hours of 50 MPa, and after 28 days of 94 MPa. Next, a slurry was prepared under the same conditions except that 0.1 4 weight of TEA cement was added to the mixing water. The onset of solidification was extended to 60 minutes and the processability was visibly improved (the slurry had a free-flowing character). The slurry prepared according to the invention had the following strengths: 2 hours after solidification of 8 MPa, 4 hours after solidification of 10 MPa and 6 hours after solidification of 20 MPa, after 24 hours a pressure strength of 66 MPa and after 28 days of 99 MPa.

Example 11 A slurry w = 0.24 was prepared from BS cement DG 430 (pure) with the addition of 1 Na ₂ CO 2 and 0.85% monosaccharide-free sodium ligninsulfonate. 0.1 µl TEA (clinker weight) was added to the mixing water. The onset of solidification of this slurry was significantly prolonged (to more than 8 hours) relative to the process without the addition of TEA to the mixing water.

Example 12.

BS cement SL 470 (pure) was used to prepare the slurry. Sulphonated ferric polyphenolate was added as an additive and mixed with 5% TEA prior to drying. The dried material was dissolved in water at a concentration of 0.4% by weight of the cement together with 1% Na ₂ CO ₂ prior to slurry preparation. The slurry had a setting time of 50 minutes and reached the following strengths: 2 hours after solidification of 5 MPa, 6 hours after solidification of 29.3 MPa, and 24 hours of 66 MPa. Using the original polyphenolate which was not dried with TEA, the following results were achieved: onset of solidification

CS 270 602 B1 minutes, compressive strength after 2 hours of solidification of 2 MPa, 6 hours of solidification of 12 MPa, 24 hours of solidification of 61.5 MPa. ·, I i

Example 13 · *,

Mortar (1: 3, 3 fractions) was prepared from BS cement Lochkov 630 (0.03 TEDB) at w = 0.27 and additives 1% ?8.00ρ 0.64 4 sulfonated sodium ferric polyphenolate and 0.07% TEA (all from cement weight). The start of mortar solidification was after 90 minutes.

For the same cement mortar was prepared Střeleč sand (0-2 mm) poměru.cement:: sand 1: ³ w 2.5 at 0.30 with the same additives. When 0.05 TEA was added to the mixing water, the onset of solidification was 40 minutes. Without the addition of TEA to the mixing water, the onset of solidification was only 25 minutes. *

Example Д4,

Slurries were prepared from BS cement lochkov 590 (0.1 4 ETG) with the addition of 0.4 4 sulfonated sodium ferric polyphenolate and 1% Na 2 CO 4. The properties of the slurries are in the following table:

w TEA was not added to the mixing water into the mixing water, the TEA start solidification viscosity was added the beginning of solidification viscosity 0.22 30 minutes more than 3.3 Passport 50 minutes 2,23 Pas 0.24 40 minutes 1.60 Pas 60 minutes 1,4 Pas 0.25 50 minutes 1,0 Pas 80 minutes 0,9 Pas Example 15

A slurry w = 0.24 was prepared from BS cement SK 580 (Pure) with the addition of 1.2 4 Na 2 CO 3 and 0.85% oxidized sodium lignin sulphonate. This slurry had an onset of solidification after 5 hours and reached a compressive strength of 24 MPa after 24 hours. However, the same slurry, when 0.1 4 TEA (to the weight of the cement) was added to the mixing water, had an onset time of more than 8 hours and reached a compressive strength of 56 MPa after 24 hours. By adding TEA to the mixing water, processability was visibly improved.

The process according to the invention can be advantageously used in the construction industry, in particular when good workability of the prepared cement mixtures is required while achieving high initial strengths.

Claims (1)

Process for preparing a gypsum-free cement mixture comprising Portland cement clinker having a specific surface area of 220 to 700 m ² / kg, a grinding additive such as ethylene glycol or dodecylbenzenesulfonic acid triethanolamide, an alkaline compound such as carbonate, bicarbonate or silicate, and sulfonated polyelectrolyte %, such as ligninsulfonate, sulfonated polyphenolate or sulfonated lignin, characterized in that 0.01 to 0.3% by weight of triethanolamine dissolved in 20 to 55% by weight of mixing water is added to the mixture, the weight percent being based on the weight of the clinker.