KR100893585B1 - Cement aid for early strength enhancement - Google Patents

Abstract

A cement additive is provided to be added when clinker is crushed in order to increase production efficiency, save energy and secure early compressive strength and long-term strength. A cement additive comprises diamine compounds represented by the formula 1. In the formula 1, A1, A2, A3 and A4 are independently -OH or -OCOCH3 wherein at least two -OCOCH3 are selected. The cement additive additionally contains alkanolamine compound and/or mixture aiding agent. The Mixture aiding agent is selected from the group consisting of diethylene glycol, triethylene glycol, polyethylene glycol, buthoxyethylene glycol, ethoxydiglycol, 1-metylpyrrolidone, ropylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, glycerine, diglycerin, triglycerin, polyglycerin, diethanolamine, triethanolammine, polyethanol amine, diisopropanolamine, triisopropanolamine, N,N-bis-(2-hydroxyethyl)-2-propanolamine and N,N-bis-(2-hydroxypropyl)-N-(hydroxyethyl)amine.

Description

Cement aid for early strength enhancement to improve grinding efficiency and early compressive strength

The present invention is added when crushing the clinker to increase the production efficiency and energy cost per unit time, give early compressive strength and long-term strength on the surface, or when the cement site casting, the characteristics of early compressive strength, long-term strength, hydration promotion For cement additives.

Clinker is produced by firing at 1300 ℃ or more in cement production process, and the clinker is crushed into ball mill and roller mill by wet and dry method. In general, cement is useful in various forms as a binder or an adhesive in the construction and civil engineering materials. Particularly known cements are first class Portland cements, which are widely used in most construction and civil engineering applications. When the one kind of Portland cement is mixed with water as a hydraulic cement, it forms a dough and gradually solidifies and hardens with time. These cements are further mixed with sand to form mortar, mixed with sand (grain aggregate), coarse aggregate, and water to produce concrete, and the products of these cements depend on the quality and properties of hydraulic cement.

This portland cement is produced by milling the clinker. Clinker is prepared by calcining a mixture of components comprising calcium carbonate, aluminum oxide, silicon dioxide, and mixed iron oxide. Chemical reactions occur during the firing process to form hardened nodules, commonly referred to as clinkers. After the clinker is cooled, it is ground with a small amount of gypsum (CaSO ₄ ) or slag in the finishing mill to obtain a uniform powdery product known as Portland cement.

In the past, most of the grinding aids were unsaturated fatty acids, amines, alcohols, and amides having low polymerization degree, such as diethyleneglycol (DEG) and glycol alkanolamines. Likewise, the grinding capacity (output per unit time) was improved and physically adsorbed to the cement particles, thereby improving the strength and physical properties of the cement.

U.S. Patent No. 4,943,323 discloses a method of partially mixing triethanolamine (TEA) with triisopropanolamine (TIPA) and using it as a grinding aid. U.S. Patent No. 6,290,772 discloses a method of mixing triisopropanolamine (TIPA) with diisopropanolethanolamine (EDIPA) and isopropanoldiethanolamine (DEIPA) and using them as grinding aids. Korean Patent Registration No. 10-0596507 discloses a method of using a compound substituted with acetic acid or a carboxyl group having 2 to 4 carbon atoms, sulfate, and ester group in TEA and TIPA as an additive for grinding aid. Korean Patent No. 10-0650135 discloses a method of mixing glycol and alkanolamine in polypropylene ethanolamine and performing the additive as a grinding aid. In this patent, the grinding aid additive is added in an amount of 0.002 to 0.2% by weight based on the weight of the clinker to improve the physical properties of the Portland cement. The alkanolamine compound prevents the ferric hydroxide produced during hydration from being precipitated into the gel at high pH when it is added as a grinding aid additive to form a complex with iron and undergoes the hydration reaction of iron aluminate. Induce to improve the strength of cement. Until now, the additives used as the grinding aids described above have been explained on the basis of the mechanism importance due to the binding relationship between iron and amine and on the hydrophilic / lipophilic (HLB) theory.

However, although the improvement of the grinding efficiency and productivity of the clinker has been improved to some extent, there is a demand for a grinding aid having a function of maximizing the grinding efficiency, water loss, workability, early compression strength, and long-term strength at the same time.

The present invention is to provide a cement additive to maximize the grinding efficiency, water loss, workability, early compression strength as well as dispersibility in order to meet the needs as described above.

Specifically, it is used for grinding cement clinker to improve grinding efficiency, quality and productivity, and at the same time, it is used as a grinding aid to further improve early compression strength, long-term strength, and hydration promotion, or it is added in the manufacture of cement composition to reduce viscosity and workability. It is an object of the present invention to provide a cement additive that can be used as a admixture having improved, early compressive strength, long term strength, and hydration promotion.

More specifically, the hydrophilicity of the amine compound used as a grinding aid in the grinding process of Portland cement is improved, and furthermore, the clinker particles and the grinding aid particles can be improved by utilizing steric hindrance due to the compactness of functional groups and molecular structure and electrical properties. Adsorption of particles and mutual electrical repulsion effect between particles enhances dispersibility and improves grinding efficiency, and meets high strength based on amine compound, and early compressive strength to improve cement quality and production competitiveness by saving energy and cost It is to provide a cement additive that represents.

The present invention relates to a cement additive for simultaneously improving the grinding efficiency, workability, water loss, early compression strength, and to a cement additive used as a grinding aid or admixture.

In particular, the present invention relates to a new cement additive capable of maximizing the grinding efficiency and early compressive strength at the same time.

More specifically, the present invention relates to a cement additive which uses an amine compound alone or further includes any one or more selected from alkanolamine compounds or auxiliary agents. For example, the amine compound and the alkanolamine compound may be mixed and used, the amine compound and the adjuvant may be mixed, or the amine compound and the alkanolamine compound and the adjuvant may be used. .

In particular, in order to simultaneously satisfy the grinding efficiency and early compression strength, it is more preferable to use a mixture of the amine compound and the alkanolamine compound, and when used in combination to increase the electrostatic repulsive force due to steric hindrance It can improve acidity, satisfy grinding function, early compressive strength expression, and hydration promotion function.

The auxiliary agent means a compound known as a conventional grinding aid, and by using the mixture with the mixture of the amine compound and the amine compound and the alkanolamine compound disclosed in the present invention can further improve their effects.

The mixing ratio thereof is not limited. Specifically, 5 to 95% by weight of the amine compound and 5 to 95% by weight of the alkanolamine compound are used, and the amine compound is used when the amine compound and the auxiliary agent are mixed. 5 to 95% by weight of the adjuvant and 5 to 95% by weight of the adjuvant, and when the amine compound, the alkanolamine compound and the adjuvant is used, the amine compound 5 ~ 90% by weight, alkanolamine compound 1 ~ 90 weight% and 1 to 90 weight% of adjuvant are mixed and used.

In the present invention, the amine-based compound uses any one selected from the diamine compound of Formula 1 and the amine compound of Formula 2 or a mixture thereof.

[Formula 1]

에서 선택되며, 단, A₁ 내지 A₄에서 선택되는 2개 이상이

이다.)(The A ₁ to A ₄ is independently -OH or

Wherein at least two selected from A ₁ to A ₄

to be.)

[Formula 2]

에서 선택되며, 단, A₅ 내지 A₇에서 선택되는 2개 이상이

이다.)(The A _{5 To} A ₇ is independently -OH or

Wherein at least two selected from A ₅ to A ₇

to be.)

기를 가지고 있는 것을 사용하며, 이러한 화합물을 사용하는 경우 분산성이나 물에 대한 친화도가 높아 클링커 분쇄 시 분쇄효율이 높아 시간당 생산효율이 높아지고, 에너지를 절감시킨다. 또한 이렇게 제조된 시멘트는 상기 물질이 시멘트표면에 코팅되어 있어 몰탈 작업 시 높은 감수효과로 강도를 높여줄 수 있고, 동시에 점도를 저하시켜 흐름성을 높여줄 수 있어 작업성이 좋아진다.In the present invention, two or more of the substituents

In the case of using such a compound, the dispersibility or affinity for water is high, and thus the grinding efficiency is high when clinker is crushed, thereby increasing the production efficiency per hour and saving energy. In addition, the cement thus manufactured is coated on the surface of the cement, so that the strength can be increased by high water-resistance effect during the mortar operation, and at the same time, the viscosity can be lowered to increase the flowability, thereby improving workability.

The alkanolamine-based compound uses any one or a mixture of two or more selected from the following Chemical Formulas 3 to 6.

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

In the alkanolamine-based compound, the -OH functional group serves to adsorb clinker particles, and the methyl group having steric hindrance and electrical repulsive force adheres to the dispersed particles so as not to condense and disperse them so as to be lubricated and pulverized per unit time. It saves time and evens out the particle size. Premature compression strength can be improved by using the compound which has isopropanol and a methanol group simultaneously here.

In the present invention, the auxiliary agent is a conventionally known grinding aid except for the amine compound or the alkanolamine compound disclosed in the present invention, and when used in combination, the grinding efficiency may be further improved. As long as the material helps the grinding efficiency and strength, the kind thereof is not limited, but for example, diethylene glycol (DEG), triethylene glycol, polyethylene glycol, butoxydiethylene glycol, ethoxydiglycol, 1-methylpyrrolidone , Propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, glycerin, diglycerin, triglycerine, polyglycerol, diethanolamine, triethanolamine, polyethanolamine, diisopropanolamine, triisopropanolamine (TIPA), N Any one or a mixture of two or more selected from N-bis- (2-hydroxyethyl) -2-propanolamine, N, N-bis- (2-hydroxypropyl) -N- (hydroxyethyl) amine use.

The present invention is added to the clinker grinding process using the cement additive as a grinding aid, to increase the grinding efficiency, or to be used alone or mixed with other additives as a cement admixture in order to increase the early compression strength to achieve the desired early compressive strength I can regulate it.

In the present invention, when the cement additive is used as a grinding aid when the cement clinker is crushed, it is preferable to add 0.0005 to 5 parts by weight based on 100 parts by weight of the clinker. If the amount is less than 0.0005 parts by weight, the effect is insignificant, and if it is more than 5 parts by weight, it is not preferable because the flocculation and entanglement occurs in the cement manufacturing process, thereby improving the efficiency of the pulverization.

In addition, the cement additive of the present invention is preferably used in the range of 0.1 to 50% by weight of the total admixture content when used as a admixture. If the amount is less than 0.1% by weight, the effect is insignificant, and when the amount is more than 50% by weight, the strength and the physical property decrease.

In addition, if the additive is commonly used in the art is not limited and may be used by adding more. For example, a reducing agent such as lignin, naphthalene polymer, melamine, polycarboxylic acid or the like may be further added.

The composition used as the grinding aid is coated on the particle surface of the finely ground clinker, so that the dispersibility is improved when used for cement.

The present invention can provide a cement additive that satisfies basic grinding efficiency, viscosity reduction, water loss, workability, early compression strength, and long-term strength at the same time, and the cement additive of the present invention can be used as a clinker grinding aid or admixture.

The cement additive according to the present invention is expected to be able to shorten the construction period by expressing the early compressive strength when used in the construction of buildings for special purposes such as harbors, dams, airports, high-rise buildings.

Hereinafter, the present invention will be described by way of example for specific description of the present invention, but the present invention is not limited to the following examples.

[Examples 1 to 4 and Comparative Examples 1 to 5]

When used as a grinding aid

In the present invention, the experiment was conducted by adding the same amount to the same clinker of Table 1 and then pulverized and compared the particle size and grinding efficiency.

Table 2 shows the powder and residues according to the compound for the grinding aid. 20 kg of the cement clinker was mixed with 0.02 parts by weight (4 g) of the compound as defined in the following examples and comparative examples, followed by diluting by adding 5 times (20 g) of water to the grinding aid and grinding for 30 minutes. The mill used a drum mill of a drum size Φ 500 × 600 mm and a rotation speed of 40 rpm.

Powder degree was performed by the KS L 5106 method, and the residue was measured using a 44 μm sieve.

[Table 1] Cement Clinker Components

[Table 2] Powder Diagram for Grinding Aids

[Formula 7]

[Formula 8]

[Formula 3]

* TIPA: triisopropanolamine

* DEG: diethylene glycol

As shown in Table 2, when the compounds of Examples 1 and 2 were added, it was found that the powderiness was high and the residue amount was low.

On the other hand, Comparative Examples 1, 2, 3, and 4 had a powder degree and a residue amount of about 10% lower than those of the Example material. In particular, in the case of Comparative Example 1 it can be seen that the case of one acetate ester substituent is more low in the powder compared to Comparative Examples 2 to 4 usually used as a grinding aid. When the grinding aid was not added as in Comparative Example 5, the powder was also low and the residue was very high. In general, when the amount of residue is high, the efficiency of the continuous pulverization production in a closed circuit in which a classifier is used is shown, and the lower the amount, the more preferable, and more preferably, the residue should be 10 or less.

[Examples 5 to 8 and Comparative Examples 6 to 10]

Condensation and mortar compressive strengths were measured at intervals of 1, 3, 7, and 28 days using the finely ground cement prepared in Examples and Comparative Examples. After the specimen was prepared by mixing with a standard yarn according to KS L 5100 and 5109, the compressive strength was measured according to the KS L 5105 method. The water / cement ratio was 0.485, and the compressive strength was measured every 1, 3, 7, 28 days using a mold of 5 × 5 × 5 cm 3.

Table 3. Mortar compressive strength

As shown in Table 3, the compressive strength was found to be excellent in Examples 5 to 8, the strength was also affected by the powder and residue amount.

As compared with Comparative Example 6 in which one acetate group was used, it was found that Example 5 using two was significantly higher not only in crushing efficiency but also in compressive strength, and particularly high in early compression strength. In addition, it can be seen that the compressive strength is further improved by using the mixture with the alkanolamine compound rather than using Formula 7 alone. It is believed that this has the effect of increasing the grinding efficiency by the presence of the polar functional group, improve the dispersibility by the electrostatic interaction to improve the final mortar compressive strength.

[Examples 9 to 12 and Comparative Examples 11 to 15]

When used as a cement admixture

Cement used 1000 g of Portland cement of Sungshin Yang, Korea, 2,450 g Jumunjin standard yarn (for compressive strength, KS L 5100) was used as the standard yarn, and Examples 1 to 4 and Comparative Examples 1 to 5 were used as admixtures. Compounds of 10% by weight were used respectively, and 90% by weight of naphthalenesulfonate was mixed and used. The content of admixture was used at 0.05% by weight relative to the cement content. Water was added thereto so that the water / cement ratio was 0.485, followed by mixing to make a mold of mortar 5 × 5 × 5 cm 3. The early compressive strength was measured every 1, 3, 7, and 28 days.

Table 4. Early compressive strength using cement additive as admixture

As shown in Table 4, when the cement composition according to the present invention is used as a admixture, the compressive strength is increased by 30% or more than when the additive is not added, and the strength is 10% or more than that of the existing compounds TIPA and DEG. It was found to be high, and early compression strength and long-term strength were confirmed.

Claims (8)

Cement additive containing a diamine compound of the formula (1). [Formula 1]

(The A ₁ to A ₄ is independently -OH or

Provided that at least two selected from A ₁ to A ₄

to be.) The method of claim 1, The cement additive is in the diamine compound, Alkanolamine compounds; Diethylene glycol (DEG), triethylene glycol, polyethylene glycol, butoxydiethylene glycol, ethoxydiglycol, 1-methylpyrrolidone, propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, glycerin, diglycerine, Triglycerin, Polyglycerol, Diethanolamine, Triethanolamine, Polyethanolamine, Diisopropanolamine, Triisopropanolamine (TIPA), N, N-bis- (2-hydroxyethyl) -2-propanolamine, N, N Any one or two or more admixtures selected from -bis- (2-hydroxypropyl) -N- (hydroxyethyl) amine; Cement additive further comprising any one or more selected from. The method of claim 2, The alkanolamine compound is a cement additive consisting of any one or a mixture of two or more selected from formulas (3) to (6). [Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

delete The method according to any one of claims 1 to 3, The additive is added to the cement clinker grinding cement additive used as a grinding aid. The method of claim 5, The additive is a cement additive used in 0.0005 ~ 5 parts by weight based on 100 parts by weight of cement clinker. The method according to any one of claims 1 to 3, The additive is a cement additive used as a cement admixture. The method of claim 7, wherein The additive is a cement additive using 0.1 to 50% by weight of the total amount of the cement admixture.