KR101642039B1 - A composite of eco-friendly binding materials with low CO2 emission property by using waste resources, steam cured cement mortar and stem cured concrete composite comprising the same - Google Patents

Abstract

The present invention provides an eco-friendly low CO_2 binder composition using waste resources and cement mortar and a concrete composition for steam curing, including the same, which improve compressive strength of a product group of steam cured concrete while improving field applicability, and remarkably reduce an amount of carbon dioxide emission in a manufacturing stage. The eco-friendly low CO_2 binder composition using the waste resources according to the present invention includes: based on a total weight of the binder composition, (a) 20-50 wt% of ground blast furnace slag; (b) 20-50 wt% of a modified cement admixture; (c) 15-30 wt% of fly ash; (d) 10-30 wt% of an incinerated material manufactured by incinerating at least one selected from sewage sludge, dyeing sludge, and domestic waste water sludge; 5-20 wt% of neutralizing plaster; and (f) 0-5 wt% of a dispersant, wherein the (b) modified cement admixture is an admixture of 70-90 wt% of commercial ordinary Portland cement and 10-30 wt% of 3CaO·Al_2O_3.

Description

FIELD OF THE INVENTION The present invention relates to an environmentally friendly low-carbon binder composition using waste materials, a cement mortar for use in the curing process, and a cement mortar and a concrete composition containing the same. same}

The present invention relates to an environmentally friendly low carbon binder composition using waste materials, and a cement mortar and concrete composition for steam curing including the same.

Various forms of global efforts to prevent global warming (adopted in 1997 and ending in Kyoto in 2005, which came into effect in 2005) are being carried out. In December 2007, the Bali Roadmap was adopted in Bali, Indonesia. Negotiations for the new climate change treaty were held until 2009, and in December 2015, plans for dealing with global climate change were established. The Paris Convention, which presents a variety of measures for the As a result, global emissions of greenhouse gases such as carbon dioxide must be reduced drastically.

The cement industry is a major carbon dioxide emission industry, along with the steel industry. For example, when producing 1 ton of cement, which is the base of concrete production, it produces about 0.9 tons of carbon dioxide. Therefore, in the cement industry, it is urgently required to develop an effective method for reducing carbon dioxide emissions.

Specifically, cement production is about 60 million tons per year, resulting in about 54 million tons of carbon dioxide emissions. Therefore, in order to reduce the generation of carbon dioxide, researches for replacing the main component of cement with industrial byproducts have been continuously carried out.

Domestic and foreign blast furnace slag and fly ash are partially mixed with cement and applied to concrete, but this method has a limit to reduce carbon dioxide remarkably.

The theory of alkaline activation cement (concrete) by polymerization reaction was conceptually established by Davidovits (France) in 1978 using kaolinite minerals and a structure similar to that of zeolite. It was not practicable because of.

Conventional techniques for producing concrete using only coal ash without using any cement include a method capable of securing a strength of 30 MPa or more by inducing a reaction by destroying the glassy film of fly ash by high temperature curing process at 60 ° C or higher . However, this method was difficult to put into practical use due to energy consumption due to high temperature curing and emission of carbon dioxide.

Also, in the prior art, there is a method of using meta kaolin. However, since kaolin is calcined at 700 to 800 ° C to use meta kaolin, carbon dioxide is discharged in this process, and economical efficiency is poor and it is difficult to put into practical use.

In addition, studies on alkali active binders, which are blended with blast furnace slag or fly ash as a partial substitute for cement and have enhanced strength performance by using an alkali activator, have been actively studied at home and abroad. Until now, the cement - based alkali active binders which have been studied for the purpose of developing eco - friendly materials in the concrete field are cement - alkaline active concrete mainly using sodium silicate as an activator, and a compounding strength model is also proposed.

However, in the case of cement-alkaline activated concrete using sodium silicate as an activator, the initial fluidity rapidly disappears and rapidly tends to increase as the amount of the alkali activator added to secure the required strength increases, .

Korean Patents 10-0855686 and 10-1014869 and Korean Concrete Institute have reported that using blast furnace slag or fly ash alone or in combination and using alkaline activators such as liquid NaOH and KOH having high alkalinity, A method of making a concrete composition is disclosed. However, the cement mortar and concrete composition by this method shows environmental damage due to the strong alkali property due to the alkali activator when mixed with blast furnace slag or fly ash. In addition, due to the ability of the strong alkali to absorb water, it is difficult to use it in a dried state such as dry cement mortar, and in the case of wet readymix concrete, a separate facility for addition of a strong alkali agent is required. There is a problem.

 Korean Patent No. 10-1488147 discloses a low temperature calcined cement based binder composition which is obtained by calcining at a temperature lower than the production conditions of general cement produced at a sintering temperature of 1,450 degrees Celsius or by activating the reaction of blast furnace slag / RTI > However, this invention has a disadvantage in that the initial hydration characteristics of the blast furnace slag can not exhibit the same or better physical properties as compared with general cement, and the use range thereof is extremely limited.

 Accordingly, there is a need to develop a technology for a carbon-emission-reduction eco-friendly binder which can solve the above-described problems.

Korean Patent No. 10-0855686 Korean Patent No. 10-1014869 Korean Patent No. 10-1488147

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems of the prior art,

By replacing cement by using waste resources, it improves compressive strength of steam curing concrete product group such as brick, interlocking brick and shore block, improves field application such as quickness characteristic, loss of fluidity, , A cement mortar for steam curing and a concrete composition containing the same.

 It is also an object of the present invention to provide an environmentally friendly low-carbon binder composition that efficiently recycles waste resources and greatly improves economy and environment-friendliness without using an alkali activator at all, and a cement mortar and concrete composition for steam curing including the same .

The present invention is based on the total weight of the binder composition,

(a) 20 to 50% by weight of blast furnace slag;

(b) 20 to 50% by weight of a modified cement admixture;

(c) 15 to 30% by weight of fly ash;

(d) 10 to 30% by weight of an ash produced by incinerating at least one selected from sewage sludge, dyeing sludge, and domestic wastewater sludge;

(e) 5 to 20% by weight of neutralized gypsum;

(f) 0 to 5% by weight of a dispersant; Lt; / RTI >

Wherein the modified cement mixture (b) is a mixture of 70 to 90% by weight of commercially available ordinary Portland cement and 10 to 30% by weight of calcium trioxide / aluminum oxide (3CaO · Al ₂ O ₃ ). Thereby providing an environmentally friendly low-carbon binder composition.

In addition,

The present invention provides a cement mortar for steam curing and a concrete composition for steam curing comprising the environmentally friendly low carbon binder composition using the waste resources.

 The environmentally friendly low carbon binder composition using the waste material of the present invention is composed of various kinds of sludge, incineration ash, fly ash, blast furnace slag, and modified cement modified with a known cement material, , The binder composition of the present invention provides an effect of remarkably reducing carbon dioxide emissions because carbon dioxide is generated at 60 kg or less in the production of 100 kg of the binder composition, unlike the case where 95 kg of carbon dioxide is discharged at the time of producing 100 kg of ordinary Portland cement.

In addition, the environmentally friendly low-carbon binder composition using the waste of the present invention improves the compressive strength of the steam curing concrete product group such as cement brick, interlocking brick, and shore block, .

Further, the environmentally friendly low-carbon bond material composition using the waste resources of the present invention exhibits high initial strength and long-term strength, has a low hydration reaction heat, high chemical resistance, high freeze-thaw resistance, excellent fire resistance, And can be efficiently utilized in concrete secondary products such as bricks, blocks, and road gutters produced by the steam curing process.

 In addition, the environmentally friendly low-carbon binder material composition using the waste resources of the present invention not only can solve the problem of disposal of industrial wastes, but also can reduce the amount of carbon dioxide emissions, thereby remarkably reducing the environmental load in this field.

In addition, the environmentally friendly low-carbon binder composition using waste materials of the present invention provides excellent economical efficiency because it is easy to mass-produce silver and recycles disused resources.

Hereinafter, the present invention will be described in detail.

It will be apparent to those skilled in the art that the technical and scientific terms used herein may have other meanings as commonly understood by one of ordinary skill in the art to which the present invention belongs. Descriptions of the blurred notice function and configuration are omitted.

Also, units of% used unclearly in the present invention means weight percent.

(A) 20 to 50% by weight of blast furnace slag; (b) 20 to 50% by weight of a modified cement admixture; (c) 15 to 30% by weight of fly ash; (d) 10 to 30% by weight of an ash produced by incinerating at least one selected from sewage sludge, dyeing sludge, and domestic wastewater sludge; (e) 5 to 20% by weight of neutralized gypsum; (f) 0 to 5% by weight of a dispersant; Lt; / RTI >

Wherein the modified cement mixture (b) is a mixture of 70 to 90% by weight of commercially available ordinary Portland cement and 10 to 30% by weight of calcium trioxide / aluminum oxide (3CaO · Al ₂ O ₃ ). To an environmentally friendly low-carbon binder composition.

If the weight of the Portland cement is less than 70% by weight and the amount of the calcium oxide / aluminum oxide exceeds 30% by weight in the modified cement mixture (b), the performance of the modified cement mixture will be poor and mixing will be difficult. When the weight exceeds 90% by weight and the amount of calcium oxide / aluminum oxide is less than 10% by weight, there is a disadvantage that the development of compressive strength at the initial stage of hydration of the modified cement mixture is delayed.

As the modified cement mixture (b), it is more preferable to mix 75 to 85% by weight of commercially available ordinary Portland cement with 15 to 25% by weight of calcium trioxide / aluminum oxide (3CaO · Al ₂ O ₃ ) have.

The modified cement mixture (b) is pulverized into powder passing at least 95 wt% in a 400 mesh sieve. If the passing rate of the powder is less than 95% by weight, the initial hydration acceleration reaction is delayed and the desired compressive strength is not exhibited. It is more preferable that the powder is pulverized into a powder that passes at least 97 wt% in a 400 mesh sieve.

By using the modified cement mixture, it is possible to reduce the amount of carbon dioxide emission of about 50 to 80% by weight as compared with the case of using 100% by weight of conventional commercial Portland cement.

In the binder composition of the present invention, the blast furnace slag, which is a known cement substitute material, is contained in an amount of 20 to 50 wt%. When the blast furnace slag is contained in an amount of less than 20% by weight, the late compression strength of the cement brick or concrete product including the binder composition is lowered. When the blast furnace slag content is more than 50% by weight, The increase in price loses the economic advantage of lowering prices by competing with known Portland Cement. More preferably, the blast furnace slag is contained in an amount of 25 to 40% by weight.

The binder composition may further comprise at least one sludge selected from sewage sludge, dyeing sludge, and incineration residues of incineration of domestic wastewater sludge, and the sludge may be contained in an amount of up to 30% by weight based on the total weight of the binder composition More preferably from 10 to 30% by weight, and even more preferably from 15 to 25% by weight.

When the sludge is contained in an amount exceeding 30% by weight, the bonding performance of the binder composition is deteriorated. If it is contained in an amount of less than 10% by weight, the environmental and economic effects to be additionally obtained are insignificant.

The dyeing sludge means sludge generated in a dyeing plant.

In the binder composition of the present invention, the fly ash, which is a known cement substitute material, may be contained in an amount of 15 to 30% by weight. Fly ash can be used, for example, generated in a fluidized bed boiler and discarded. The fly ash provides advantages such as fluidity improvement, long-term strength enhancement, reduction of hydration heat, inhibition of alkali aggregate reaction, resistance to sulfate, improvement of watertightness of concrete, and replacement of relatively expensive cement, .

When the fly ash is included in the above range, workability is improved, curing heat is lowered, and long-term strength and water tightness are improved.

In the binder composition of the present invention, the incineration ash is reacted with a fluidized bed boiler ash or fly ash to promote the pozzolanic reaction to improve the compressive strength Function. The ash can be contained in an amount of 10 to 30% by weight. When the ash is contained within the above range, the pozzolanic reaction is promoted by reacting with the fluidized bed boiler ash and fly ash, thereby achieving the same effect as improving the compressive strength. If the incineration ash content is less than 10% by weight, the effect of the pozzolanic reaction is weak and it is difficult to contribute to the improvement of the compressive strength. When the incineration ash content exceeds 30% by weight, the initial compressive strength can be lowered.

In the binder composition of the present invention, the neutralized gypsum may be discharged from a phosphoric acid fertilizer process, for example. The neutralized gypsum may be included in an amount of 5 to 20% by weight. When the neutralized gypsum is contained in an amount of less than 5 wt%, the reactivity of the gypsum is less so that the initial compressive strength can be inhibited. If the amount of the gypsum is more than 20 wt%, mixing is difficult due to a rapid hydration reaction. More preferably 7 to 15% by weight.

In the binder composition of the present invention, the dispersant may be added because the mixing may be difficult due to a rapid hydration reaction when the materials are mixed, and may not be added when there is no possibility of such a problem occurring. As the dispersing agent, citric acid and the like can be used. The dispersant is preferably contained in an amount of 5 wt% or less.

The binder composition of the present invention may further comprise at least one sludge selected from sewage sludge, dyeing sludge, and domestic wastewater sludge.

Further, according to the present invention,

The present invention relates to a cement mortar for steam curing comprising an environmentally friendly low-carbon binder composition using waste resources of the present invention. The binder composition may be contained in an amount of 20 to 50% by weight based on the total weight of the steam cured cement mortar, more preferably 25 to 45% by weight.

The steam curing mortar can be used for the production of steam curing concrete products such as cement bricks, interlocking bricks, and revetment blocks.

Further, according to the present invention,

The present invention relates to a concrete composition for steam curing comprising an environmentally friendly low-carbon binder composition using waste materials of the present invention. The binder composition may be contained in an amount of 20 to 50 wt%, more preferably 25 to 45 wt%, based on the total weight of the concrete composition for steam curing.

Hereinafter, the present invention will be described in more detail by way of examples. However, the following examples are intended to further illustrate the present invention, and the scope of the present invention is not limited by the following examples. The following examples can be appropriately modified and changed by those skilled in the art within the scope of the present invention.

Production Examples 1 to 3: Preparation of Modified Cement Mixture

The components were mixed so as to have the compositions shown in Table 1 below, and then pulverized into powders passing at least 95 wt% in a 400 mesh sieve to prepare a modified cement mixture.

Production Example 1  Production Example 2 Production Example 3 Usually Portland Cement 75 80 85 Calcium trioxide, aluminum oxide (3CaO.Al2O3) 25 20 15 total 100 100 100

(Unit: wt%)

Examples 1 to 6: Preparation of Environmentally Friendly Low-Carbon Binder Composition Using Waste Resources

The composition was mixed with the modified cement mixture of Table 1 so as to have the composition shown in Table 2 below to prepare an environmentally friendly low carbon binder composition using waste materials. In Comparative Example 1, ordinary Portland cement was used.

Example Comparative Example One 2 3 4 5 6 One Usually Portland Cement 0 0 0 0 0 0 100 Blast furnace slag 25 30 25 30 25 30 0 Modified cement mixture Production Example 1 Production Example 1 Production Example 2 Production Example 2 Production Example 3 Production Example 3 30 25 30 25 30 25 0 Fly ash 20 20 20 20 20 20 0 Incinerator 15 15 15 15 15 15 0 Chinese plaster 7 10 7 10 7 10 0 Chemical dispersant
(Citric acid) 3 0 3 0 3 0 0 total 100 100 100 100 100 100 100

(Unit: wt%)

Note) Incineration ash: Sewage sludge of Bucheon city is incinerated and used as incinerator

Test Example : Eco-friendly Using Waste Resources Low carbon Binders  Evaluation of physical properties of composition

In order to measure the compressive strength of the specimen, the specimen was prepared by the steam curing process generally used in the production of cement brick or shore block. The weight ratio of the binder composition of the present invention (or the cement of the comparative example) to the sand was 1: 3 by weight, and the weight ratio of the binder composition of the present invention (or the cement of the comparative example) was 1: 0.4. Each material was mixed with water, mixed and agitated with a motor mixer for 3 minutes, molded into a mold of 40 × 40 × 160 mm, and cured at room temperature (20 ± 3 ° C.) for 24 hours. After 24 hours, the mold was demolded and cured for 10 hours at 60 ± 5 ° C and 90% humidity. At this time, the rate of temperature increase up to 60 占 폚 was set to 10 占 폚 per hour to prevent the rapid temperature rise. The specimens cured for 10 hours were taken out from the moisture curing chamber and then air-cured at room temperature (20 ± 3 ° C) for 24 hours. The final cured specimens were measured for compressive strength according to the KSL ISO 610 standard. Specific experimental results are shown in Table 3 below.

Example Comparative Example One 2 3 4 5 6 One Compressive strength (unit: MPa) 27.1 27.9 28.1 27.7 27.2 28.1 24.2

As can be seen from the above Table 3, in the case of the test specimens prepared using the environmentally friendly low-carbon bond material compositions using the waste resources of Examples 1 to 6 of the present invention, the test specimens prepared by using the general cement of Comparative Example 1 Compressive strength.

The spirit of the present invention should not be construed as being limited to the embodiments described, and all the equivalents or equivalents of the claims, as well as the following claims, fall within the scope of the present invention.

Claims (5)

With respect to the total weight of the binder composition,
(a) 20 to 50% by weight of blast furnace slag;
(b) 20 to 50% by weight of a modified cement admixture;
(c) 15 to 30% by weight of fly ash;
(d) 10 to 30% by weight of an ash produced by incinerating at least one selected from sewage sludge, dyeing sludge, and domestic wastewater sludge;
(e) 5 to 20% by weight of neutralized gypsum;
(f) 0 to 5% by weight of a dispersant; Lt; / RTI >
Wherein the modified cement mixture (b) is a mixture of 70 to 90% by weight of commercially available ordinary Portland cement and 10 to 30% by weight of calcium trioxide / aluminum oxide (3CaO · Al ₂ O ₃ ) A binder composition for environmentally friendly low - carbon steam curing. The method according to claim 1,
Wherein the modified cement mixture (b) is pulverized into a powder passing at least 95 wt% in a 400 mesh sieve. The method according to claim 1,
Wherein the binder composition further comprises at least one sludge selected from sewage sludge, dyeing sludge, and domestic wastewater sludge. A cement mortar for steam curing comprising the environmentally friendly low carbon steam curing binder composition according to claim 1.  A concrete composition for steam curing comprising a binder composition for environmentally friendly low-carbon steam curing using the waste of claim 1.