KR20120107834A - High active cement clinker and high active cement - Google Patents

Abstract

PURPOSE: A high-activated cement clinker and cement with high activity are provided to enhance hydration performance to be equal to or higher than early strength Portland cement. CONSTITUTION: A high-activated cement clinker becomes a parent of an early strength type cement based solidifier or early strength type cement. The ratio of Bogue type mineral composition is C3S>70%. When the hydraulic modulus of the cement clinker with high activity is 2.2-2.3, the silica modulus is 1.7-2.4 and iron modulus is 1.0-2.1. When the hydraulic module is less than 2.1-2.2, the silica modulus is 1.5-2.0 and the iron modulus is 0.9-1.4. The activity factor of the cement with high activity is 2.9-3.8. A manufacturing method of the cement with high activity comprises a step of adding 1.5-4.0 wt% of gypsum to the cement with high activity in an SO3 conversion.

Description

HIGH ACTIVE CEMENT CLINKER AND HIGH ACTIVE CEMENT}

The present invention relates to a crude steel cement used for building and civil engineering-related cement products, such as crude cement-based solidified materials, concrete blocks, siding boards, concrete piles, and raw concrete, for improvement of soft soils and contaminated soils. It relates to a highly active cement clinker as a mother, and a highly active cement by the high active cement clinker.

Conventionally, crude steel portland cement and crude steel portland cement, which are defined by JIS standards, are known to have higher C ₃ S content in cement clinker than ordinary portland cement and have good short-term strength. It is used for various uses, such as a soil improvement material, the solidifying material of a heavy metal, or a radioactive waste.

In addition, in addition to the portland cement, a variety of crude cements including C ₃ S have been developed. For example, Patent Literature 1 discloses 60 to 75 wt% of C ₃ S, 9 to 11 wt% of C ₃ A, 0 to 4 wt% of C ₂ S, 4 to 7 wt% of C ₄ AF, and C _3. A mixture of cement joints is disclosed in which early high strength is obtained at a chemical composition of 70-80% by weight S + C ₃ A and 3-8% by weight of calcium sulfate in terms of SO ₃ .

In addition, Patent Literature 2 has 40 to 80% by weight of C ₃ S, less than 20% by weight of C ₄ AF, less than 30% by weight of C ₂ S, less than 20% by weight of C ₃ A, and 1.0 to 3.0 of SO ₃ content. A portland cement clinker having a weight percent clinker phase component capable of low temperature firing and having good strength development is disclosed.

In addition, Patent Literature 3 discloses a cement composition having a C ₃ S amount of 60 to 80 mass%.

On the other hand, when manufacturing (firing) a cement clinker, three types of control indexes, such as cement quality, productivity, and stable firing of cement clinker, are known as three factors, such as hydraulic modulus (HM), silicic acid ratio (SM), and iron ratio (IM). Modulus (also called "chemical modulus", "purification", etc.) is used. Coefficients of activity (A.I.) may be added to them.

For example, Patent Document 4 discloses high-strength concrete using cement clinker having 60 wt% or more (up to 68 wt% in the example) of C ₃ S at HM = 2.20 to 2.40, SM = 2.3 to 3.0, and IM = 1.5 to 2.5. A method for producing a member is disclosed. In addition, Patent Document 5 discloses a cement clinker that uses a large amount of coal ash having a hydraulic ratio (HM) of 1.8 to 2.0, a silicic acid ratio (SM) of 1.8 to 2.3, and an iron ratio (IM) of 1.8 to 2.8 as raw materials.

In this regard, in the crude steel Portland cement clinker close to the highly active cement clinker of the present invention, the hydraulic modulus (HM) is 2.2-2.3, the silicic acid ratio (SM) is 2.7-2.8, the iron ratio (IM) is 1.7-1.9, In Portland Cement Clinker, the fineness is reduced to 6000 cm 2 / g in the range of crude steel Portland Cement Clinker.

Japanese Patent Application Laid-Open No. 06-340455 Publication No. 10-512841 Japanese Patent Laid-Open No. 2008-133139 Japanese Patent Application Laid-Open No. 59-30740 Japanese Patent Application Laid-Open No. 2000-281399

As shown in Patent Literatures 1 to 3, there are high C ₃ S cement clinkers. However, in view of these examples, more than 70% was hardly obtained. In addition, the thing about patent document 1 is a special cement, it is inadequate for general building civil engineering materials and ground improvement materials, and manufacturing requires a complicated particle size control with energy cost. Because many low-temperature firing is the SO ₃ component in the Patent Document 2, and the SO _X (sulfur oxides) generated in the exhaust gas is difficult to stable baked clinker. In particular, it is difficult to use waste as part of the raw material (combined raw material) of the cement clinker. Moreover, Patent Documents 1 to 3 do not describe in detail the method for producing a cement clinker.

Moreover, as shown in patent documents 4 and 5, it is known to manufacture cement clinker using management indexes, such as a hydraulic ratio (HM), silicic acid ratio (SM), and an iron ratio (IM), and also the range of each index value is also however been found in accordance with the type of cement, the amount of C ₃ S does not been shown for the cement clinker of over 70%, also it can not be said that the amount of C ₃ S and greater than 70% has been established a method for producing cement clinker activity.

The present invention aims to solve the problems as described above, the general purpose high C ₃ S> 70% high activity cement clinker which is the base material of the crude cement-based solidifying material or crude cement, and manages to manufacture it efficiently The purpose is to provide an index value (modulus value).

The high-activity cement clinker according to claim 1 of the present application is "a high-activity cement clinker which becomes a matrix of a rough cement-based solidifying material or a rough cement, and wherein the ratio of mineral composition in the Bogue formula is C ₃ S> 70%, When the hydraulic modulus (HM) in the high-activity cement clinker is 2.2 to 2.3, the silicic acid ratio (SM) is 1.7 to 2.4, the iron modulus (IM) is 1.0 to 2.1, and the hydraulic modulus (HM) is less than 2.1 to 2.2. Is a highly active cement clinker characterized by having a silicic acid ratio (SM) of 1.5 to 2.0 and an iron ratio (IM) of 0.9 to 1.4.

The high activity cement clinker has a high hydration activity, and the peak value of the hydration exotherm rate of the cement by the cement clinker to the conduction calorimeter is larger than that of the cement by the clinker corresponding to the crude steel cement clinker, and the amount of hydration calorific value Refers to more cement clinker than that of cement by clinker corresponding to crude steel cement clinker.

Crude cement type solidifying material is a solidifying material containing cement used for ground improvement, heavy metal leaching inhibition, radioactive waste treatment, etc., and refers to a solidifying material having better short-term strength than ordinary cement. In addition, crude cement is a cement or cement composition having the same strength expression as that of crude steel portland cement, and in addition to the highly active cement obtained by simply adding gypsum to the highly active cement clinker, fly ash and silica are applied to the highly active cement. The crude steel mixed cement which mixed any one of powder and slag, and the crude steel cement composition which mixes two or more known inorganic admixtures with the said high active cement are mentioned. In this specification, cements are divided into "rough cement type solidifying material" and "rough cement", and the rough cement is a broad concept including three kinds of high active cement, rough mixed cement, and rough cement composition.

The high activity cement clinker of the present invention has a C ₃ S> 70% ratio of mineral composition in the Bogue formula. Below 70%, it becomes equivalent to the conventional crude steel cement clinker or the super-steel cement clinker, and it becomes difficult to satisfy the intention of the present invention to obtain a cement clinker having a higher hydration activity than these. C ₂ S amount is not particularly limited, it is preferred that the C ₂ S <5%. The rest is a gap phase mainly composed of calcium aluminate system.

The high-activity cement clinker of the present invention is also managed by the same hydraulic rate (HM), silicic acid rate (SM) and iron ratio (IM), but the range of silicic acid rate (SM) and iron ratio (IM) is the same as the conventional cement clinker. Based on the range of HM), we found that it is better to divide into two. This is to distinguish as Since the scope of hydroponic rate (HM) silica ratio (SM) and cheolryul (IM) is the C ₃ S> 70% by a range of different termination, by separating this manner C ₃ S> 70% a The range of modulus in order to become clear can be achieved.

One of the classifications is when the hydrolysis rate (H.M.) is 2.2 to 2.3, the silicic acid rate (S.M.) is 1.7 to 2.4, and the iron ratio (I.M.) is 1.0 to 2.1. When the hydraulic yield (H.M.) exceeds 2.3, the amount of free lime is increased significantly, and it becomes difficult to obtain stable high quality high activity cement clinker with stable clinker firing. If it is less than 2.2, if the appropriate range of silicic acid rate (S.M.) is not corrected, the appropriate range becomes narrow within the above range, and stable clinker firing becomes difficult and stable high quality high activity cement clinker becomes difficult to obtain.

In the range of said hydraulic ratio HM, silicic acid rate SM is 1.7-2.4. If it is less than 1.7, the amount of free lime is remarkably increased, and stable clinker firing may be difficult. If it exceeds 2.4, C ₃ S> 70% may not be obtained. In addition, iron content (IM) is 1.0-2.1. If the iron modulus (IM) is in this range, a stable high quality high activity cement clinker of C ₃ S> 70% can be obtained.

The other one of the divisions is that when the hydraulic ratio (HM) is less than 2.1 to 2.2, the silicic acid ratio (SM) is 1.5 to 2.0 and the iron ratio (IM) is 0.9 to 1.4. If the hydraulic modulus (HM) is less than 2.1, it is difficult to obtain a cement clinker of C ₃ S> 70%. If it is 2.2 or more, if the appropriate range of silicic acid rate SM is not corrected, the appropriate range will become narrow within the said range, stable clinker baking will become difficult, and stable high quality high activity cement clinker will become difficult to obtain.

In the range of said hydraulic ratio HM, silicic acid rate SM is 1.5-2.0. If it is less than 1.5, the amount of free lime is remarkably increased, and stable clinker firing may be difficult. If it exceeds 2.0, C ₃ S> 70% may not be obtained. In addition, iron content (IM) is 0.9-1.4. If the iron modulus (IM) is in this range, a stable high quality high activity cement clinker of C ₃ S> 70% can be obtained.

The high activity cement clinker which concerns on Claim 2 of this application is "the high activity cement clinker of Claim 1 characterized by the activity coefficient (A.I.) in said high activity cement clinker being 2.9-3.8."

The activity coefficient (AI) is the same index as the silicic acid rate (SM), and the control coefficient is controlled by adding an activity coefficient to the above three modulus as a control index, thereby controlling the stability of C ₃ S> 70%. It is easier to obtain high quality high activity cement clinker. Standard values for Portland cement clinker are 3.8-4.8. On the other hand, in the high activity cement clinker of this invention, it is 2.9-3.8, Preferably it is 3.1-3.8 when the hydraulic ratio (HM) is 2.2-2.3, and it is 2.9-3.6 when the hydraulic ratio (HM) is less than 2.1-2.2. , by setting the range of C ₃ S> and 70%, number of C ₂ S it is easier to obtain a (C ₂ S <5%) of the present invention highly active cement clinker which is extremely less in.

In addition, the amount of free lime in the high activity cement clinker of the present invention is preferably 0.5 to 7.5% by weight. If the firing temperature is not lowered at less than 0.5 wt%, the brick inside the kiln may be damaged when firing in a cement kiln. If it exceeds 7.5% by weight, there is a fear that abnormal swelling may be caused by hydration of free lime. The amount of sulfuric acid component is preferably less than 1% by weight in terms of SO ₃ . By less than 1% by weight and to reduce the SO _X (sulfur oxide) amount in the exhaust gas.

And according to claim 3 of the present application is an active cement "and formed by the addition to 1.5? 4.0% by weight of gypsum to the above claim 1 or claim 2 and according to the active cement clinker with SO ₃ in terms of active cement".

Since the high activity cement of the present invention is based on the high activity cement clinker, it has a hydration activity as rough as that of crude steel portland cement. In addition, since it is not bound to the conventional cement standard, it is difficult to use for portland cement or the like, where the cement standard should be considered. However, cement solidified material for soil improvement, solidified material for waste treatment, block or siding board It is a special hardening material that can be used for cement products.

The high activity of cement is preferably a high activity with respect to the plaster of cement clinker from 1.5? 4.0% by weight in terms of SO _3. If less than 1.5% by weight, C ₃ A in the cement clinker may be quenched and sufficient working time may not be secured when producing the concrete product. If it exceeds 4.0% by weight, there is a fear that expansion occurs due to unreacted gypsum after curing of the cement.

The high activity cement clinker of the present invention has a larger amount of C ₃ S compared to a crude steel-type cement such as conventional crude steel portance cement. Therefore, a high stable hydration performance can be obtained over the crude steel portland cement from the initial hydration to the long term. Moreover, various cement materials, such as a crude steel mixed cement mixed with high active cement, a fly ash, and blast furnace slag, a low temperature cement composition, and a roughening cement type solidifying material, can be manufactured using these as a matrix.

In addition, by using the modulus value (each range of the hydrodynamic rate, silicic acid rate, and iron rate) of the present invention, quality stability can be achieved even in a high active cement clinker having a C ₃ S> 70%.

In addition, the high-active cement of the present invention has a hydration activity above the crude steel portland cement, but is not bound to the conventional cement standards, so ground improvement material, cement building material production, off-size concrete, mortar cement, other cement-based solidified material, blast furnace cement And it is a high versatility that can be used for a variety of applications, mainly the mother cement of mixed cements such as fly ash cement.

Hereinafter, the present invention will be described in more detail.

[Highly active cement clinker]

Highly active cement clinker of the present invention and the same cement clinker in the conventional early-strength portland cement clinker, the amount of C ₃ S by Borg (Bogue) of cement clinker formula is C ₃ S> 70% large as compared with the conventional general cement clinker will be. Since it is high C ₃ S, it has high hydration activity. The meaning of "high activity" is as having mentioned above.

The Vogue equation has been used to calculate the main mineral composition in cement clinker conventionally, and the ratio of each mineral is calculated from the analysis result of chemical composition. The ratios obtained are estimates based only on the results of analysis of the chemical composition and do not correspond to the actual ratios in the cement clinker. Moreover,% is mass%.

[Bogue Formula]

C ₃ S is a mineral that is the main cause of cement strength development from short-term age to long-term age, so the more they are, the higher the strength or crude steel. Although C ₂ S does not contribute much to the development of strength as a short-term age, it contributes to the development of strength as a long-term age for continuing hydration over a long term, and the more they are, the better the increase in strength as a long-term age with less fever. Moreover, it becomes excellent in chemical resistance and dry shrinkage.

C ₃ A has high hydration activity and greatly contributes to strength expression as a short-term age. However, if there are many of them, the increase in strength as a long-term age becomes bad due to rapid rigidity. Moreover, hydration heat generation is high and it is inferior to chemical resistance and dry shrinkage.

Although C ₃ AF does not stand out as a hydration performance, it contributes to reverse firing as a gap phase in clinker firing.

In the present invention, C ₃ S> 70% is to obtain a cement having a very high initial hydration activity, and when C ₃ S is 70% or less, it is difficult to obtain a crude steel cement having a hydration activity equivalent to or higher than that of a conventional steel cement. Lose. Although an upper limit is not specifically limited, 85% or less is preferable.

If it exceeds 85%, the amount of free lime may also increase remarkably, and the quality stability of the cement clinker may not be maintained. Also, the more active the sign language is not available, a lot of calcium minerals in the aluminate-based, such as high C ₃ A, due to the consideration of long-term strength development, wokeobilriti (workability), and durability.

High activity of the present invention, the cement clinker is made by the clearance of the C ₂ S with the calcium aluminate-based in addition to the C ₃ S as the main component. The gap includes minerals of C ₃ A, C ₃ AF augmentation. The remainder is amorphous gap phase and the like.

In addition, the composition of the high-activity cement clinker of the present invention depends on the modulus of the hydraulic modulus (HM), the silicic acid ratio (SM), the iron modulus (IM), and the activity coefficient (AI), which are used as management indicators in the manufacture of the cement clinker (firing). Can be determined. The method of the regulation can be calculated from the components of SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ , and CaO, which are the major chemical components of cement clinker, and are closely related to raw material components and inverse plasticity, This is because it may be manufactured or limited in consideration of the quality of the cement clinker.

』으로 나타내고, 모듈러스 중에서도 가장 중시되는 지표이다. 수경률이 클수록 시멘트 클링커 중의 산화칼슘량 및 C₃S량이 많아진다. 이 때문에 강도 발현성이 좋아지나, 한편으로 소성 반응성은 저하된다. 시멘트 클링커의 소성 반응성이 저하되면 유리된 석회량이 많아지고, 잔존하게 됨과 함께 연료 원단위가 증대된다. 보통 시멘트 클링커의 수경률은 2.0?2.2 정도이다. The hydraulic rate (HM) is

It is an index most important among modulus. The larger the hydraulic yield, the greater the amount of calcium oxide and C ₃ S in the cement clinker. For this reason, intensity | strength developability improves, but plastic reactivity falls on the other hand. When the plasticity reactivity of the cement clinker decreases, the amount of free lime increases and remains, and the fuel raw unit increases. Usually, the cementation rate of cement clinker is about 2.0-2.2.

In the high-activity cement clinker of the present invention, it is 2.1 to 2.3, but is classified into two types of less than 2.1 to 2.2 and 2.2 to 2.3 in relation to silicic acid rate (SM) and iron ratio (IM). In this way, since the optimum ranges of the silicic acid rate SM and iron ratio IM which become C ₃ S> 70% differ according to the range of the hydraulic modulus (HM), it is easy to manufacture by dividing in this way, and C _In order to be able to surely obtain ₃ S> 70%, the range of the optimum modulus must be cleared to obtain the said effect. Using either of the modulated modulus values, a cement clinker of C ₃ S> 70% can be obtained. Dividing the use of this division can be suitably selected according to the chemical composition of the cement clinker raw material to be used. For example, when the hydraulic modulus (HM) is selected to be less than 2.1 to 2.2, the raw material composition can be reduced by reducing the raw unit of limestone which is the main raw material and suppressing CO ₂ emissions during firing.

』로 나타내고, 소성의 안정성이나 C₂S의 생성량에 크게 관계한다. 규산율(S.M.)이 크면, 소성이 원활하게 진행되기 위해서 필요한 융액의 양이 적게 되어 소성이 어려워지므로 소성 온도가 높아지는 경향이 있다. 그 결과, 소성 설비가 손상되기 쉬워진다. 시멘트 클링커는 C₂S가 풍부한 것이 되므로, 저 발열성으로 장기 재령으로의 강도 발현에 우수한 시멘트를 제조할 수 있다. 한편, 규산율(S.M.)이 너무 작으면 융액의 양이 많아지므로, 킬른 내벽의 코팅(coating)양의 증감에 의해 원료의 폐색[코팅 트러블(coating trouble)]을 일으킬 우려가 생긴다. 보통 시멘트 클링커의 규산율(S.M.)은 2.4?2.8이다. The silicic acid rate (SM) is

It represents a "strongly related to the generation amount of the sintering stability and the C ₂ S. When the silicic acid rate SM is large, the amount of melt required for the smooth progress of the baking becomes small, and the baking becomes difficult, so that the firing temperature tends to increase. As a result, the firing equipment tends to be damaged. Since the cement clinker is rich in C ₂ S, it is possible to produce cement excellent in the development of strength at long age with low exotherm. On the other hand, if the silicic acid rate SM is too small, the amount of melt increases, so that there is a fear that raw material clogging (coating trouble) is caused by increasing or decreasing the amount of coating on the inner wall of the kiln. Usually the silicic acid rate (SM) of cement clinker is 2.4 ~ 2.8.

In the high activity cement clinker of this invention, silicic acid rate SM changes with hydraulic diameter HM. This is because the scope of hydroponic rate (HM) silica ratio (SM) where the C ₃ S> 70% by a range of different. When the hydraulic ratio (HM) is 2.2 to 2.3, the silicic acid ratio (SM) is 1.7 to 2.4, and when the hydraulic ratio (HM) is less than 2.1 to 2.2, the silicic acid ratio (SM) is 1.5 to 2.0. Such a range is as described above.

Thus, in the high activity cement clinker of this invention, compared with the conventional cement clinker, silicic acid rate SM is low and it becomes a high C ₃ S. low C ₂ S cement clinker. Therefore, a stable high hydration activity can be obtained from the beginning of hydration without relying on unstable high hydration activity by calcium aluminate minerals such as C ₃ A in the early stage of hydration.

』로 나타내고, 시멘트 클링커의 간극상의 조성에 크게 관계한다. 철률(I.M.)이 크면, 산화 알루미늄량이 늘어나서 알루미네이트량이 증가하기 때문에 단기 재령으로의 강도 발현은 좋아지나, 수화 초기의 안정성이나 화학 저항성에 다소 부족한 시멘트가 된다. 보통 시멘트 클링커의 철률(I.M.)은 1.9?2.1이다. The iron yield (IM) is

It is largely related to the composition of the gap phase of a cement clinker. When the iron modulus (IM) is large, the amount of aluminum oxide increases and the amount of aluminate increases, so that the strength is improved at a short age, but the cement is somewhat insufficient in the stability and chemical resistance at the beginning of hydration. Usually the iron modulus (IM) of cement clinker is 1.9 to 2.1.

In the high activity cement clinker of this invention, iron modulus (IM) also changes with a hydraulic modulus (HM). This is because the range of the iron ratio IM, which becomes C ₃ S> 70%, varies depending on the range of hydraulic modulus HM. When the hydraulic modulus (HM) is 2.2 to 2.3, the iron modulus (IM) is 1.0 to 2.1, and when the hydraulic modulus (HM) is less than 2.1 to 2.2, the iron modulus (IM) is 0.9 to 1.4. Such a range is as described above.

Thus, in the high activity of cement clinker of the present invention, as compared with the conventional cement clinker low cheolryul (IM), it is a little low C ₃ A cement clinker of the trend. This is the same as above, is highly active cement clinker and C ₃ S in the present invention, hydration, it is possible to obtain a stable high hydration activity from the early, such as the hydration activity of the for-age C ₃ A as in the conventional cement clinker This is because there is no need to rely on unstable high hydration activity by calcium aluminate minerals.

』로 나타내고, 규산율(S.M.)과 동일한 지표이며, 특히 실리카 성분과 알루미나 성분과의 균형(balance)을 보는 것이다. 보통 시멘트 클링커에서의 표준적인 값은 3.8?4.2이다. Moreover, in the high activity cement clinker of this invention, it is preferable to make activity coefficient (AI) into 2.9-3.8. The coefficient of activity (AI) is

It is the same index as the silicic acid rate (SM), and especially the balance of a silica component and an alumina component is seen. Usually the standard value for cement clinker is 3.8-4.2.

In the high activity cement clinker of the present invention, the active coefficient (AI) is preferably 2.9 to 3.8 which is lower than that of the conventional cement clinker, more preferably 3.1 to 3.8 when the hydraulic modulus (HM) is 2.2 to 2.3, When (HM) is less than 2.1-2.2, it is 2.9-3.6. By this range, C ₃ S> and 70%, number of C ₂ S is easier to obtain a (C ₂ S <5%) of the present invention highly active cement clinker which is extremely less in.

Furthermore, in the high activity cement clinker of the present invention, it is preferable that the amount of free lime in the cement clinker is 0.5 to 7.5% by weight, and the amount of sulfur component is less than 1% by weight in terms of SO ₃ . The high activity cement clinker of the present invention is high C ₃ S, but in order to further increase the hydration activity of C ₃ S, the calorific value is excessively increased, and free lime is present in the above range in order to increase the molding temperature. The above range is as described above. In addition, since the sulfur component contributes to the hydration control of calcium aluminate-based minerals and the formation of ettringite, there is little presence in the clinker in the conventional cement clinker. The amount of sulfur component is preferably less than 1% by weight in terms of SO ₃ since it depends on C ₃ S and free lime and does not depend very much on calcium aluminate minerals.

[Production of Highly Active Cement Clinker]

(1) Raw material

Limestone, clay, silica, iron and the like, which are conventionally used as the main raw materials for clinker, can be used in the same manner as in the prior art. In addition, in the present invention, it is preferable to use a calcium-rich industrial waste containing 20% by weight or more in terms of CaO of a calcium component which has not undergone much reuse.

Examples of industrial wastes containing 20% by weight or more of calcium in terms of CaO are desulfurized slag by molten iron pretreatment, desulfurized slag from which iron is removed by selecting it as a magnet, converter slag from which iron is removed by reduction treatment, waste siding waste, etc. Waste building materials, PS ash, concrete sludge and the like.

These industrial wastes can be used to replace some of the limestone or clay. The amount of addition to the cement fired raw material is based on the chemical composition of limestone and clay, but preferably 400 kg or less per ton of cement clinker. If more than 400 kg per 1t of cement clinker is added, impurities may increase, which makes the clinker firing difficult or adversely affects the quality of the resulting cement clinker. When industrial waste is replaced with a part of limestone and used, it also leads to the reduction of carbon dioxide emission, and therefore it is preferable from the viewpoint of reducing the environmental load.

Mineralizers (mineralizers and fluxes) have the effect of lowering the firing temperature of the cement clinker. By adding this to the raw material, the firing becomes easy even in a high C ₃ S cement clinker where C ₃ S> 70%. Mineralizers include fluorspar, gypsum, and combinations thereof. In addition, industrial wastes containing sulfur and fluorine, such as desulfurized slag, can also be used. If the content of fluorine in the cement clinker is too high, problems such as fluorine elution and delay in condensation will occur. Therefore, the use of a large amount of mineralizer is not preferable. If desulfurized slag is used as part of the cement clinker raw material, the mineralizer may not be required.

(2) raw material process

Production of the combination raw material in the raw material step is carried out in the same manner as in the prior art. For example, as needed, each dry raw material is mix | blended in a predetermined | prescribed ratio, it mixes and grinds in a raw material mill, and is temporarily stored in a blending silo. The temporarily stored mixed raw materials are mixed again to the desired chemical composition, and the final combination of the chemical compositions is carried out and stored in a storage silo.

Chemical composition management is carried out in the same manner as in the prior art at the hydraulic ratio (HM), the silicic acid ratio (SM) and the iron ratio (IM), so that they are within the scope of the present invention described above. Then, it is checked whether the activity coefficient AI is within the scope of the present invention. If out of range, recombine. Since CaO, SiO ₂ , Al ₂ O ₃ and Fe ₂ O ₃ do not volatilize or dissipate during clinker adjustment, these modulus values in the raw materials of the combination become modulus values in the cement clinker.

(3) firing process

The combined raw material sent from the storage silo is fired by the method similar to the conventional method using the conventional cement baking equipment, and the high activity cement clinker of this invention is obtained.

As for a baking temperature, 1250-1600 degreeC is preferable. Below 1250 ° C., the production of C ₃ S itself is impossible. In addition, when it exceeds 1600 degreeC, it will interfere with the baking of the cement clinker, such as the refractory inside a rotary kiln.

Clinker cooling, crushing, etc. after baking are the same as before. The obtained highly active cement clinker of this invention becomes a base material of a roughening cement type solidifying material or a roughening cement.

[Use of Highly Active Cement Clinker]

The obtained high-active cement clinker of the present invention can be used as a high-active cement to be described later by adding gypsum or as a crude steel cement composition in which a known inorganic admixture is mixed with high-active cement, but it can also be used without cement.

For example, a highly active cement clinker is used as a fine powder with a blain value of 4000 cm 2 / g or more, and used as a single component by adding a coagulation / hardening modifier to them, or further, a blast furnace slag powder or the like. Silica fume is mixed and used as a clinker composition. By diluting with fine limestone powder, fly ash or the like, the strength characteristics and fluidity can be designed freely. The main uses include grout materials, coating materials, waste treatment materials and the like.

[Highly active cement]

The high-active cement of the present invention is obtained by adding gypsum to 1.5-4.0 wt% in terms of SO ₃ to the above-mentioned high-active cement clinker, and mixing and grinding with a grinding mill or the like together with the grinding aid. The process and the apparatus are the same as those of the mapping process in conventional cement production. Gypsum and grinding aid are also the same as those used in conventional cement production.

The amount of gypsum added is 1.5 to 4.0% by weight in terms of SO ₃ . If the content is less than 1.5% by weight, C ₃ A in the cement clinker may be suddenly quenched to ensure sufficient working time when producing a concrete product or the like. When it exceeds 4.0 weight%, there exists a possibility that expansion may occur with unreacted gypsum after hardening of cement.

The powder degree is not particularly limited, but 3000 cm 2 / g or more is preferable in terms of the blain value.

The high-active cement of the present invention is a kind of crude steel cement as defined in the present specification, and may be used as a concrete secondary product, a siding board or a mortar cement as it is. When used, it becomes a crude cement-based solidified material.

When mixed with any one of fly ash, silica powder, and slag, crude steel mixed cement, such as crude steel fly ash, crude steel silica cement, crude silica fume cement, and crude blast furnace cement, is obtained.

Moreover, when mixing multiple types of inorganic admixtures, it will become a crude steel cement composition. Although the crude steel cement of the present invention has a hydration activity equivalent to that of crude steel portland cement, but is not a JIS standard product, it cannot be used where a JIS standard product is required, but it can be used in many fields requiring roughness.

[Hydration Activity Verification Test of Highly Active Cement Clinker (Highly Active Cement)]

Test firing of the high activity cement clinker according to the present invention in an electric furnace, and gypsum was added to the obtained high activity cement clinker to obtain the high activity cement of the present invention, and the calorific activity of the highly active cement was measured by conduction calorimeter and JIS mortar. It confirmed by the compressive strength test by.

(1) Raw material used

Table 1 shows the types and chemical components of the raw materials used.

(2) Raw material combination

Table 2 shows the blending of the raw materials in the respective cement cement clinkers. Mixing was adjusted so that the amount of C ₃ S, modulus, and the like of each cement cement clinker became the values shown in Table 3.

Tense 1, tense 9, and tense 10 are comparative products, and tense 2 to 8 are examples of the present invention. In addition, the numerical value in a table | surface is a raw unit. The combination was carried out by drying each raw material at 100 ° C., pulverizing with a disk mill and mixing in a mortar.

(3) Cement Clinker Firing

Each sample in which the raw materials were combined by the above formulation was pelletized into a particle diameter of about 30 mm, and the pellets were placed in an electric furnace, and the temperature was raised to 10 ° C./min, and maintained at 1450 ° C. for 3 hours to be fired. . The obtained prototype clinker was taken out of the electric furnace, left in the room, quenched, and then pulverized to pass through a 75 μm sieve with a 250 rpm ball mill.

Chemical composition analysis was carried out for each pulverized product, and the modulus (ratio coefficient) in each prototype cement clinker, the amount of C ₃ S, the amount of C ₂ S, the amount of C ₃ A, and the amount of C ₄ AF based on the Vogue equation The amount was calculated. These results are shown in Table 3. In addition,% in a formula is weight%.

(4) Measurement of heat of hydration by high activity cement

Gypsum (calcium sulfate dihydrate in a premium reagent) was added to the above-mentioned prototype clinker in the amount of SO _{3 in} terms of SO ₃ to prepare a highly active cement or the like. The comparative product of the prototype 1 is a crude steel cement equivalent product, and the examples of the prototypes 2 to 8 are the high-active cement of the present invention.

Cement paste was prepared by adding distilled water of W / C = 50% to each prototype cement, and the hydration exothermic rate of the cement paste was measured by a conduction calorimeter. Evaluation was carried out with a calorific value up to 7 days of age. The results are shown in Table 4.

As indicated above, it was found that all of the embodiments (Tensins 2 to 8) of the present invention had a large amount of calorific value and a high hydration activity as compared with Sample 1, which is a crude steel cement equivalent.

(5) compressive strength test

JIS mortar was produced using the prototype cements, such as the highly active cement produced as mentioned above, and the compressive strength test was done on the 1st, 3rd, 7th and 28th days in accordance with JIS R 5201. The results are shown in Table 5.

As shown in the above table, the embodiment of the present invention (Temperatures 2 to 8) is at least 1 which is a crude steel cement equivalent product, and has good strength expression and high activity from short-term to long-term ages.

Claims (3)

Joganghyeong cement and is a derivative of the fire or joganghyeong cement, Borg (Bogue) hydroponic rate in the high activity of cement clinker according to the proportion of the mineral composition C ₃ S> 70% of the high activity of cement clinker of the formula (HM ) Is 2.2? 2.3, silicidation rate (SM) is 1.7? 2.4, iron ratio (IM) is 1.0? 2.1, and hydroponicity rate (HM) is less than 2.1? 2.2, and silicic acid rate (SM) is 1.5? 2.0. High activity cement clinker, characterized in that the iron (IM) is 0.9 ~ 1.4. The method of claim 1,
High activity cement clinker characterized in that the activity coefficient (AI) in the high activity cement clinker is 2.9 ~ 3.8. Any one of claims 1 to 1.5? And obtained by the addition to the 4.0 wt% active cement 2, wherein the active cement clinker SO ₃ converting the gypsum in and described.