KR102632870B1 - CO2 sequestraion method with concrete slurry water using rapid carbonation reaction of supercritical CO2 - Google Patents
CO2 sequestraion method with concrete slurry water using rapid carbonation reaction of supercritical CO2 Download PDFInfo
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- 239000004567 concrete Substances 0.000 title claims abstract description 66
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 61
- 238000000034 method Methods 0.000 title claims abstract description 13
- 239000002002 slurry Substances 0.000 title 1
- 238000011084 recovery Methods 0.000 claims abstract description 31
- 239000007787 solid Substances 0.000 claims description 29
- 238000005516 engineering process Methods 0.000 abstract description 10
- 229910052799 carbon Inorganic materials 0.000 abstract description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 abstract description 5
- 238000003860 storage Methods 0.000 abstract description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 18
- 239000004568 cement Substances 0.000 description 16
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 13
- 239000011575 calcium Substances 0.000 description 12
- 229910002092 carbon dioxide Inorganic materials 0.000 description 9
- 239000007789 gas Substances 0.000 description 9
- 239000011395 ready-mix concrete Substances 0.000 description 9
- 238000004519 manufacturing process Methods 0.000 description 8
- 238000005259 measurement Methods 0.000 description 7
- 229910000019 calcium carbonate Inorganic materials 0.000 description 6
- 229910052500 inorganic mineral Inorganic materials 0.000 description 6
- 239000007788 liquid Substances 0.000 description 6
- 239000011707 mineral Substances 0.000 description 6
- 239000002245 particle Substances 0.000 description 5
- 239000010802 sludge Substances 0.000 description 5
- 238000003756 stirring Methods 0.000 description 5
- 238000001139 pH measurement Methods 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 3
- 238000010276 construction Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 239000001569 carbon dioxide Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000010828 elution Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 229910021532 Calcite Inorganic materials 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 239000003929 acidic solution Substances 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000005431 greenhouse gas Substances 0.000 description 1
- 230000003100 immobilizing effect Effects 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 239000013081 microcrystal Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000003472 neutralizing effect Effects 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 238000001878 scanning electron micrograph Methods 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F11/00—Compounds of calcium, strontium, or barium
- C01F11/18—Carbonates
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/40—Valorisation of by-products of wastewater, sewage or sludge processing
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Abstract
본 발명은 초임계 CO2의 급속 탄산화 반응을 통해, 레미콘 회수수를 각종 산업계에서 배출, 포집되는 CO2의 고정원으로 활용하는 CCUS(Carbon Capture Utilization and Storage) 기술에 관한 것이다.
본 발명은 「포집된 CO2를 초임계 상태로 레미콘 회수수에 주입되어, 초임계 CO2에 의한 레미콘 회수수 내 Ca(OH)2의 급속 탄산화 반응에 의해 CaCO3가 생성되도록 하는, 레미콘 회수수로 다량 CO2를 고정하는 방법」을 제공한다.The present invention relates to CCUS (Carbon Capture Utilization and Storage) technology that utilizes ready-mixed concrete recovery water as a fixed source of CO 2 discharged and captured in various industries through the rapid carbonation reaction of supercritical CO 2 .
The present invention is a ready-mixed concrete recovery method in which "the captured CO 2 is injected into the ready-mixed concrete recovery water in a supercritical state, and CaCO 3 is produced by the rapid carbonation reaction of Ca(OH) 2 in the ready-mixed concrete recovery water by supercritical CO 2 . Provides “a method for fixing large amounts of CO 2 in waterways.”
Description
본 발명은 초임계 CO2의 급속 탄산화 반응을 통해, 레미콘 회수수를 각종 산업계에서 배출, 포집되는 CO2의 고정원으로 활용하는 CCUS(Carbon Capture Utilization and Storage) 기술에 관한 것이다. The present invention relates to CCUS (Carbon Capture Utilization and Storage) technology that utilizes ready-mix concrete recovery water as a fixed source of CO 2 discharged and captured in various industries through the rapid carbonation reaction of supercritical CO 2 .
국내·외적에서 CO2 포집기술이 상당한 수준(포집율 90%, CO2 농도 87%)으로 개발되고 있다. 머지않아 탄소중립을 실현하기 위해서 전 산업에서 CO2 포집기술이 상용화 될 것으로 예상된다. CO2 capture technology is being developed at a significant level both domestically and internationally (capture rate of 90%, CO2 concentration of 87%). It is expected that CO2 capture technology will soon be commercialized across all industries to achieve carbon neutrality.
시멘트 산업은 전 세계 CO2 배출량의 약 8%를 차지하고 있는 고탄소 배출업종이다. 전세계적으로 2050 탄소중립을 실현하기 위하여 다양한 연구 및 이행전략을 수립 중에 있으며, 시멘트 산업에서도 온실가스 배출 저감을 위한 다양한 노력을 하고 있다. 시멘트 산업에서는 혼합시멘트 사용 확대, 킬른의 열효율 증대를 위한 연료전환 등 CO2 감축을 위한 노력을 실시하고 있으나 감축할당량을 채우기에는 매우 부족한 실정이며, 혁신적인 CO2 감축을 위해서는 광물탄산화와 같은 CCUS(Carbon Capture Utilization and Storage) 기술 개발이 필수적이라고 보고되고 있다.The cement industry is a high-carbon emission industry, accounting for approximately 8% of global CO2 emissions. A variety of research and implementation strategies are being established worldwide to achieve carbon neutrality by 2050, and the cement industry is also making various efforts to reduce greenhouse gas emissions. The cement industry is making efforts to reduce CO2 , such as expanding the use of mixed cement and switching fuels to increase the thermal efficiency of kilns, but it is insufficient to meet the reduction quota. In order to achieve innovative CO2 reduction, CCUS (Carbon Carbonation) such as mineral carbonation is needed. It is reported that the development of Capture Utilization and Storage technology is essential.
일반적인 광물탄산화 반응은 이산화탄소가 액상에 용해되어 반응이 이루어지지만 반응속도가 매우 느려 효율적이지 못하다. 그러나 일정한 온도조건(31.1℃ 이상) 및 압력조건(73.8 bar)에서 형성되는 초임계 CO2는 밀도와 용해력이 액체와 같고, 점도와 확산도는 기체와 같다고 알려져 있으며, 물에서 초임계 CO2의 용해도는 자연탄산화 조건에서보다 약 10배 높기 때문에 일반적인 광물탄산화 대비 반응성 극대화로 인한 탄산화 반응이 가속화 된다.In the general mineral carbonation reaction, carbon dioxide is dissolved in a liquid phase, but the reaction rate is very slow and is not efficient. However, it is known that supercritical CO 2 formed under certain temperature conditions (above 31.1℃) and pressure conditions (73.8 bar) has the same density and solubility as liquid, and has the same viscosity and diffusivity as gas, and the solubility of supercritical CO 2 in water is is about 10 times higher than under natural carbonation conditions, so the carbonation reaction is accelerated due to maximum reactivity compared to general mineral carbonation.
외국에서는 위와 같은 초임계 CO2를 활용하여 다양한 광물탄산화 연구가 진행된 이력이 있으며 대다수의 연구에서 제시된 반응조건으로는 온도조건 80℃ 이내, 압력조건 150bar 이내로 설정하고 있다. 선행 연구에서는 탄산화 반응시 초임계 CO2 상태에서는 온도의 영향은 큰 차이가 없으나 압력이 증가함에 따라 탄산화 효율이 증가한다고 보고된 바 있다. In foreign countries, various mineral carbonation studies have been conducted using supercritical CO 2 as described above, and the reaction conditions suggested in most studies are set at a temperature condition within 80°C and a pressure condition within 150 bar. In previous studies, it has been reported that there is no significant effect of temperature in the supercritical CO 2 state during the carbonation reaction, but that carbonation efficiency increases as pressure increases.
또한, 종래에 순환골재의 pH 저감을 통한 성·복토재로서의 재사용을 위하여 CO2를 가스 혹은 액상형태로 순환골재에 교반하여 중성화를 실시한 연구가 있다. 다만, 이러한 방식은 골재 표면에서만 반응이 일어나도록 한 것이기 때문에 CO2 다량 고정화에는 부합하지 않는다.In addition, there has been research in the past where CO 2 was stirred into recycled aggregate in gas or liquid form to neutralize it in order to reduce the pH of recycled aggregate and reuse it as filler/cover material. However, this method is not suitable for immobilizing large amounts of CO 2 because the reaction occurs only on the surface of the aggregate.
한편, 레미콘 생산과정에서는 필연적으로 레미콘 회수수가 발생한다. 레미콘 회수수는 아래 [참고도 1]에 도시된 바와 같이 상징수와 슬러지 고형분으로 구성되어 있으며 미수화 시멘트 입자를 다량 함유하고 있어 강알칼리성의 건설폐기물로 분류된다. 이러한 레미콘 회수수는 토양과 수질을 오염시킬 수 있으므로 중화처리하거나 필터프레스 등 재활용 설비를 구비하여 적법하게 처리될 것이 요구된다.Meanwhile, in the ready-mixed concrete production process, ready-mixed concrete recovery inevitably occurs. As shown in [Reference Figure 1] below, ready-mix concrete recovered water is composed of solid water and sludge solids and contains a large amount of unhydrated cement particles, so it is classified as strongly alkaline construction waste. Since this ready-mixed concrete recovery water can contaminate soil and water, it is required to be treated legally by neutralizing it or using recycling facilities such as a filter press.
[참고도 1][Reference 1]
그러나 레미콘 회수수는 시멘트 성분에 기인한 Ca2+ 성분을 다량 함유하고 있어 CO2 고정화 재료로의 활용가능성이 매우 높을 것으로 기대된다. 따라서 본 발명은 레미콘 회수수를 CO2 고정원으로 활용하고자 한 것이다.However, the ready-mixed concrete recovered water contains a large amount of Ca 2+ due to the cement component, so it is expected to have a very high possibility of being used as a CO 2 fixation material. Therefore, the present invention is intended to utilize ready-mixed concrete recovery water as a source of CO 2 fixation.
등록특허 10-1870152 "레미콘 회수수를 이용한 탄산칼슘 제조 방법", 공개특허 10-2015-0059370 "레미콘 회수수를 이용한 액상탄산화 및 그에 따른 탄산칼슘 제조방법" 등은 레미콘 회수수를 CO2 고정에 활용한 기술들인데, 이들은 레미콘 회수수 속의 Ca2+ 이온의 용출을 극대화(산성용액을 통한 용출)한 뒤 CO2를 흡수한 아민용액과 액-액 반응을 시키는 것으로 CaCO3 생산에 기술 초점이 맞춰져 있다.Registered patent 10-1870152 “Method for producing calcium carbonate using ready-mixed concrete recovered water”, published patent 10-2015-0059370 “Liquid carbonation using ready-mixed concrete recovered water and the resulting method for producing calcium carbonate” etc. use ready-mixed concrete recovered water for CO 2 fixation. The technologies used are focused on CaCO 3 production by maximizing the elution of Ca 2+ ions in ready-mixed concrete recovery water (elution through acidic solution) and then causing a liquid-liquid reaction with the amine solution that absorbs CO 2 . It's aligned.
본 발명은 강알칼리성 건설폐기물인 레미콘 회수수를 여러 산업시설에서 배출, 포집된 다량의 CO2 고정원으로 활용하여, CO2 발생을 줄이고 레미콘 회수수 처리 부담을 경감시킴은 물론, 산업상 용처가 다양한 탄산칼슘(CaCO3)을 생성토록 하는 기술을 제공함에 그 목적이 있다. The present invention utilizes ready-mixed concrete recovered water, which is a strongly alkaline construction waste, as a source of fixation of large amounts of CO 2 discharged and collected from various industrial facilities, thereby reducing CO 2 generation and reducing the burden of processing ready-mixed concrete recovered water, as well as industrial use. The purpose is to provide technology to produce various types of calcium carbonate (CaCO 3 ).
전술한 과제 해결을 위해 본 발명은 「포집된 CO2를 초임계 상태로 레미콘 회수수에 주입되어, 초임계 CO2에 의한 레미콘 회수수 내 Ca(OH)2의 급속 탄산화 반응에 의해 CaCO3가 생성되도록 하는, 레미콘 회수수로 다량 CO2를 고정하는 방법」을 제공한다.In order to solve the above-mentioned problem, the present invention is to inject the collected CO 2 into the ready-mixed concrete recovery water in a supercritical state, and CaCO 3 is converted into CaCO 3 by the rapid carbonation reaction of Ca(OH) 2 in the ready-mixed concrete recovery water by the supercritical CO 2 A method of fixing a large amount of CO 2 with recovered ready-mixed concrete is provided.
상기 레미콘 회수수는 고형분 함량이 5~25 wt%이고, 상기 고형분은 XRF 분석 시 CaO 성분이 30 wt% 이상 포함되어 있는 것을 적용할 수 있으며, 상기 급속 탄산화 반응 전·후에 pH가 12 이상에서 9.0~9.5로 낮아진다.The ready-mixed concrete recovery water has a solid content of 5 to 25 wt%, and the solid content can be applied to contain more than 30 wt% of CaO during XRF analysis, and the pH before and after the rapid carbonation reaction is 9.0 at 12 or more. It is lowered to ~9.5.
본 발명은 레미콘 회수수가 수용된 밀폐된 반응기(Reactor)에 초임계 CO2가 주입되고, 상기 반응기 내부의 온도 및 압력조건이 설정된 범위에서 유지되면서, 상기 반응기 내부 중앙에서 축회전 하는 교반기(Agitator)의 구동에 의해 상기 레미콘 회수수와 초임계 CO2가 교반되며 급속 탄산화 반응이 이루어지도록 할 수 있다.In the present invention, supercritical CO 2 is injected into a sealed reactor containing ready-mixed concrete recovery water, and the temperature and pressure conditions inside the reactor are maintained in a set range, and an agitator rotating on a shaft at the center of the reactor is provided. By driving, the ready-mixed concrete recovery water and supercritical CO 2 are stirred and a rapid carbonation reaction can be achieved.
포집된 CO2가 봄베(Bombe)에 저장되었다가 가스부스터(Gas Booster)를 거쳐 초임계 상태로, 레미콘 회수수가 수용된 밀폐된 반응기(Reactor)에 주입되도록 할 수 있고, 상기 반응기 내부는 온도 35~80℃, 압력 75~160 bar가 유지되도록 하고, 상기 교반기는 100~400 rpm으로 축회전 하고, 교반은 5~30분간 이루어지도록 할 수 있다.The collected CO 2 can be stored in a bomb and then passed through a gas booster to a supercritical state and injected into a sealed reactor containing ready-mixed concrete recovery water, and the inside of the reactor has a temperature of 35~35. 80°C and pressure of 75 to 160 bar are maintained, the stirrer rotates at 100 to 400 rpm, and stirring can be performed for 5 to 30 minutes.
본 발명에 따른 효과는 다음과 같다.The effects according to the present invention are as follows.
1. 강알칼리성 건설폐기물인 레미콘 회수수를 여러 산업시설에서 배출, 배집된 다량의 CO2 고정원으로 활용하여, CO2 발생을 줄이고 레미콘 회수수 처리 부담을 경감시킴은 물론, 산업상 용처가 다양한 탄산칼슘(CaCO3)을 생산할수 있다.1. By using ready-mixed concrete recovered water, which is a highly alkaline construction waste, as a source of fixation for large amounts of CO 2 discharged and collected from various industrial facilities, not only does it reduce CO 2 generation and reduce the burden of processing ready-mixed concrete recovered water, but it also has a variety of industrial uses. Calcium carbonate (CaCO 3 ) can be produced.
2. 초임계 CO2의 급속 탄산화 반응을 이용하므로 많은 양의 이산화탄소를 단시간에 고정시킬 수 있다.2. Because the rapid carbonation reaction of supercritical CO 2 is used, a large amount of carbon dioxide can be fixed in a short time.
3. 국내 대형 양회사들은 레미콘 사업도 병행하는 경우가 많으므로, 시멘트 공장에서 배출되는 CO2를 포집하거나 바이패스시킴으로써, 시멘트 공장에 인접한 레미콘 공장의 회수수와 연계함으로써, 시멘트 생산시 자제 발생하는 CO2의 다량 고정화가 가능하다.3. Since both large domestic companies often engage in the ready-mix concrete business in parallel, CO 2 emitted from cement plants is captured or bypassed, and by linking it with recovered water from the ready-mix concrete plant adjacent to the cement plant, the waste generated during cement production is reduced. Immobilization of large amounts of CO 2 is possible.
4. 전국 각지에서 포집된 CO2를 반응장치가 설치된 거점 인근 레미콘 공장으로 이송하여 초임계 CO2의 급속 탄산화를 통한 CO2 고정화가 이루어진다면 시멘트 산업 뿐만 아니라 전 산업에서 발생되는 CO2의 고정 및 활용이 가능하다.4. If CO 2 collected from all over the country is transported to a ready-mix concrete plant near the base where the reaction device is installed and CO 2 is fixed through rapid carbonation of supercritical CO 2 , CO 2 generated not only in the cement industry but also in all industries can be fixed and fixed. It is possible to utilize it.
[도 1]은 본 발명이 제공하는 "초임계 CO2의 급속 탄산화 반응을 이용하고, 레미콘 회수수를 고정원으로 하는 CO2 고정화 방법"의 개요 및 연구 개발 과정을 나타낸 것이다.
[도 2]는 본 발명 도출에 이용된 초임계 CO2 반응기를 촬영한 사진이다.
[도 3]은 초임계 CO2 반응기의 개요도이다.
[도 4]는 레미콘 회수수에 대한 초임계 CO2 탄산화 전·후의 pH 측정결과를 나타낸 그래프이다.
[도 5]는 고형분율 5 wt% 레미콘 회수수의 초임계 CO2 탄산화 전·후 SEM 사진이다.
[도 6]은 초임계 CO2 탄산화 전·후 슬러지 고형분의 XRD 측정결과를 나타낸 그래프이다.
[도 7]은 초임계 CO2 탄산화 전·후 슬러지 고형분의 TG-DTA 측정결과를 나타낸 그래프이다.
[도 8]은 시멘트 공장 및 레미콘 공장의 연계를 통한 레미콘 회수수를 이용한 포집 CO2 고정화 기술 개념을 도시한 것이다.
[도 9]는 레미콘 회수수를 이용한 포집 CO2 고정화 기술 개념을 도시한 것이다.[Figure 1] shows the overview and research and development process of the “CO 2 immobilization method using the rapid carbonation reaction of supercritical CO 2 and using recovered ready-mixed concrete as a fixation source” provided by the present invention.
[Figure 2] is a photograph of the supercritical CO 2 reactor used in deriving the present invention.
[Figure 3] is a schematic diagram of a supercritical CO 2 reactor.
[Figure 4] is a graph showing the pH measurement results before and after supercritical CO 2 carbonation of ready-mixed concrete recovery water.
[Figure 5] is an SEM photograph before and after supercritical CO 2 carbonation of ready-mixed concrete recovery water with a solid content of 5 wt%.
[Figure 6] is a graph showing the XRD measurement results of sludge solids before and after supercritical CO 2 carbonation.
[Figure 7] is a graph showing the TG-DTA measurement results of sludge solids before and after supercritical CO 2 carbonation.
[Figure 8] shows the concept of capture CO 2 immobilization technology using recovered ready-mixed concrete through linkage between a cement plant and a ready-mixed concrete plant.
[Figure 9] shows the concept of capture CO 2 immobilization technology using recovered ready-mixed concrete.
본 발명은 「포집된 CO2를 초임계 상태로 레미콘 회수수에 주입되어, 초임계 CO2에 의한 레미콘 회수수 내 Ca(OH)2의 급속 탄산화 반응에 의해 CaCO3가 생성되도록 하는, 레미콘 회수수로 다량 CO2를 고정하는 방법」을 제공한다(아래 [화학식 1] 참조).The present invention is a ready-mixed concrete recovery method in which "the captured CO 2 is injected into the ready-mixed concrete recovery water in a supercritical state, and CaCO 3 is produced by the rapid carbonation reaction of Ca(OH) 2 in the ready-mixed concrete recovery water by supercritical CO 2 . Provides a “method for fixing large amounts of CO 2 in water” (see [Formula 1] below).
[화학식 1][Formula 1]
Ca(OH)2 + CO2 → CaCO3 + H2OCa(OH) 2 + CO 2 → CaCO 3 + H 2 O
상기 레미콘 회수수는 고형분 함량이 5~25 wt%이고, 상기 고형분은 XRF 분석 시 CaO 성분이 30 wt% 이상 포함되어 있는 것을 적용할 수 있다. 이러한 레미콘 회수수는 급속 탄산화 반응 전·후에 pH가 12 이상에서 9.0~9.5로 낮아진다.The ready-mixed concrete recovery water has a solid content of 5 to 25 wt%, and the solid content can be applied to include more than 30 wt% of CaO component during XRF analysis. The pH of this ready-mixed concrete recovered water is lowered from 12 or higher to 9.0 to 9.5 before and after the rapid carbonation reaction.
본 발명은 레미콘 회수수가 수용된 밀폐된 반응기(Reactor)에 초임계 CO2가 주입되고, 상기 반응기 내부의 온도 및 압력조건이 설정된 범위에서 유지되면서, 상기 반응기 내부 중앙에서 축회전 하는 교반기(Agitator)의 구동에 의해 상기 레미콘 회수수와 초임계 CO2가 교반되며 급속 탄산화 반응이 이루어지도록 할 수 있다.In the present invention, supercritical CO 2 is injected into a sealed reactor containing ready-mixed concrete recovery water, and the temperature and pressure conditions inside the reactor are maintained in a set range, and an agitator rotating on a shaft at the center of the reactor is provided. By driving, the ready-mixed concrete recovery water and supercritical CO 2 are stirred and a rapid carbonation reaction can be achieved.
포집된 CO2가 봄베(Bombe)에 저장되었다가 가스부스터(Gas Booster)를 거쳐 초임계 상태로, 레미콘 회수수가 수용된 밀폐된 반응기(Reactor)에 주입되도록 할 수 있고, 상기 반응기 내부는 온도 35~80℃, 압력 75~160 bar가 유지되도록 하고, 상기 교반기는 100~400 rpm으로 축회전 하고, 교반은 5~30분간 이루어지도록 할 수 있다.The collected CO 2 can be stored in a bomb and then passed through a gas booster to a supercritical state and injected into a sealed reactor containing ready-mixed concrete recovery water, and the inside of the reactor has a temperature of 35~35. 80°C and pressure of 75 to 160 bar are maintained, the stirrer rotates at 100 to 400 rpm, and stirring can be performed for 5 to 30 minutes.
이하에서는 구체적인 시험 내용과 함께 본 발명을 상세히 설명한다.Below, the present invention will be described in detail along with specific test details.
레미콘 회수수의 고형분율에 따른 CO2 고정량을 산정하기 위하여 레미콘 회수수 채취 후 상징수와 슬러지 고형분을 분리하였으며, 상기 고형분은 건조 처리하였다. 이후 상징수와 건조 슬러지 고형분(이하 '고형분'으로 약칭)을 혼합하여 고형분율을 5, 10, 15, 20, 25 wt%로 통제하고, 초임계 CO2 반응을 활용한 광물탄산화를 실시하였다.In order to calculate the amount of CO2 fixed according to the solid content of the ready-mixed concrete recovered water, the ready-mixed concrete recovered water was collected, the solid water and the sludge were separated, and the solids were dried. Afterwards, the solid water content and dried sludge solid content (hereinafter abbreviated as 'solid content') were mixed to control the solid content ratio to 5, 10, 15, 20, and 25 wt%, and mineral carbonation was performed using supercritical CO 2 reaction.
XRF 분석에 의하여 도출된 상기 고형분의 화학조성은 아래 [표 1]과 같으며, 초임계 CO2 탄산화 반응이 가능한 CaO 성분이 약 34% 함유되어 있는 것을 확인하였다.The chemical composition of the solid content derived by XRF analysis is shown in [Table 1] below, and it was confirmed that it contained about 34% of CaO component capable of supercritical CO 2 carbonation reaction.
본 발명을 위한 연구에서 사용한 초임계 CO2 반응기(1)의 사진을 [도 2]에, 개요도를 [도 3]에 나타냈다. 초임계 CO2 반응기(1)는 본 발명 발명자가 설계하여 주문 제작한 것으로, 가스부스터(Gas Booster, 40)를 통해 반응기(Reactor, 10)에 초임계 CO2를 공급하도록 구성되어 있다. A photograph of the supercritical CO 2 reactor (1) used in the research for the present invention is shown in [Figure 2], and a schematic diagram is shown in [Figure 3]. The supercritical CO 2 reactor 1 is designed and custom-made by the inventor of the present invention, and is configured to supply supercritical CO 2 to the reactor 10 through a gas booster 40.
반응기(10)에는 온도조절을 위한 가열판(Electric Heater, 11) 및 레미콘 회수수와 초임계 CO2의 혼합을 위한 교반기(Agitator, 20)가 설치되어 있으며, 상기 교반기(20)는 반응기(10) 내부 중앙에 설치된 종축에 복수개의 교반날개(21)가 이격하여 결합되어 있고, 모터(21)에 의해 축회전하도록 구성되어 있다. 상기 반응기(10) 내부는 온도와 압력은 열전대(Thermocouple, 12)와 압력게이지(Pressure gauge, 13)를 통해 측정되도록 구성되어 있다. 상기 반응기(10)는 압력용기(Pressure vessel)로 제작하여, 커버(15) 결합으로 밀폐되도록 구성할 수 있으며, 레미콘 회수수 내 Ca(OH)2의 급속 탄산화 반응에 의해 CaCO3와 함께 생성된 물은 드레인(14)을 통해 배출되고, 미반응 CO2(Unreacted CO2)는 배기된 후 다시 포집되도록 할 수 있다.The reactor (10) is equipped with a heating plate (Electric Heater, 11) for temperature control and an agitator (20) for mixing ready-mixed concrete recovery water and supercritical CO 2. The agitator (20) is installed in the reactor (10). A plurality of stirring blades (21) are spaced apart and coupled to a longitudinal axis installed in the center of the interior, and are configured to rotate the axis by a motor (21). Inside the reactor 10, temperature and pressure are configured to be measured through a thermocouple (12) and a pressure gauge (13). The reactor 10 is manufactured as a pressure vessel and can be configured to be sealed by combining a cover 15. The reactor 10 is produced together with CaCO 3 by the rapid carbonation reaction of Ca(OH) 2 in the ready-mixed concrete recovered water. Water is discharged through the drain 14, and unreacted CO 2 (Unreacted CO 2 ) can be discharged and then collected again.
상기 가스부스터(40)는 봄베(30, Bombe)에 저장된 CO2 가스를 고압으로 가압하여 초임계 상태로 상기 반응기(10)에 주입하기 위한 장치이며, 에어컴프레셔(Air Compressor, 50)가 상기 가스부스터(40)에 추가로 연결되어 CO2의 초임계 상태를 안정적으로 유지시킬 수 있다.The gas booster 40 is a device for pressurizing the CO 2 gas stored in the bomb 30 at high pressure and injecting it into the reactor 10 in a supercritical state, and an air compressor 50 is used to compress the gas. It is additionally connected to the booster 40 to stably maintain the supercritical state of CO 2 .
고형분율을 조정한 레미콘 회수수를 대상으로 40~80℃의 온도조건, 75~160bar의 압력조건 및 100~400rpm의 교반조건에서 5~30분간 초임계 탄산화 반응을 진행한 뒤, pH 측정, TG-DTA 및 XRD 분석을 통해 고형분율이 초임계 CO2 고정화량에 미치는 영향을 확인하였다.A supercritical carbonation reaction was performed on the ready-mixed concrete recovery water with the solid content adjusted for 5 to 30 minutes at a temperature of 40 to 80°C, a pressure of 75 to 160 bar, and stirring at 100 to 400 rpm, followed by pH measurement and TG. -DTA and XRD analysis confirmed the effect of solid content on the amount of supercritical CO 2 immobilization.
1. pH 측정결과1. pH measurement results
레미콘 회수수에 대한 초임계 CO2 탄산화 전·후의 pH 측정결과를 [도 4]에 나타내었다. 반응 전 레미콘 회수수는 pH 12 이상으로 측정되었으며, 반응 후에는 고형분율에 관계없이 pH 9~9.5의 범위로 측정되었다. The pH measurement results before and after supercritical CO 2 carbonation of the ready-mixed concrete recovered water are shown in [Figure 4]. Before the reaction, the ready-mixed concrete recovered water was measured to be pH 12 or higher, and after the reaction, the pH was measured to be in the range of 9 to 9.5 regardless of the solid content ratio.
반응 전 레미콘 회수수의 경우 고형분 속 Ca(OH)2로 인해 강알칼리성을 나타내며, 초임계 CO2 반응 후에는 탄산화 반응으로 인해 pH가 저하된 것으로 판단된다.In the case of ready-mixed concrete recovery water before the reaction, it is strongly alkaline due to Ca(OH) 2 in the solid content, and after the supercritical CO 2 reaction, the pH is judged to have decreased due to the carbonation reaction.
일반적으로 고순도 CaCO3의 pH는 9.4로 알려져 있으며 초임계 CO2 탄산화 후 반응생성물의 pH가 9.0~9.5의 범위로 측정되고 있으므로, 레미콘 회수수의 Ca2+ 성분이 CaCO3로 완전히 전환된 것으로 판단된다.Generally, the pH of high-purity CaCO 3 is known to be 9.4, and since the pH of the reaction product after supercritical CO 2 carbonation is measured in the range of 9.0 to 9.5, it is judged that the Ca 2 + component of the ready-mixed concrete recovery water has been completely converted to CaCO 3 . do.
2. SEM 측정결과2. SEM measurement results
고형분율 5 wt% 레미콘 회수수의 초임계 CO2 탄산화 전·후 SEM 사진을 [도 5]에 나타내었다.SEM images of recovered ready-mixed concrete with a solid content of 5 wt% before and after supercritical CO 2 carbonation are shown in [Figure 5].
반응 전 레미콘 회수수의 경우 고형분 속 Ca(OH)2는 초임계 CO2에 의한 탄산화 반응 시 입자 표면부터 CaCO3의 미세결정층이 치밀하게 생성되고 이후 내부로 확산되어 반응이 진행되면서 완전 탄산화에 도달한다. 본 연구 결과에서도 반응 전 고형분 입자는 표면에 결정층이 없는 구형의 형태를 띄고 있으나 초임계 CO2 탄산화 반응 후 고형분에서는 입자 표면에 미세결정층이 생성된 것을 확인할 수 있었다. 이러한 미세결정층의 생성은 초임계 CO2에 의한 광물탄산화 반응 진행으로 인한 것이다.In the case of ready-mixed concrete recovered water before reaction, Ca(OH) 2 in the solid content is carbonated by supercritical CO 2. A fine crystalline layer of CaCO 3 is created densely on the surface of the particle, and then diffuses to the inside, leading to complete carbonation as the reaction progresses. reach As a result of this study, it was confirmed that the solid particles before the reaction had a spherical shape without a crystal layer on the surface, but in the solid particles after the supercritical CO 2 carbonation reaction, a microcrystal layer was created on the particle surface. The formation of this microcrystalline layer is due to the progress of mineral carbonation reaction by supercritical CO 2 .
3. XRD 및 TG-DTA 측정결과3. XRD and TG-DTA measurement results
초임계 CO2 탄산화 전·후 고형분의 XRD 및 TG-DTA 측정결과는 [도 6] 및 [도 7]에 나타내었다.The XRD and TG-DTA measurement results of solid content before and after supercritical CO 2 carbonation are shown in [Figure 6] and [Figure 7].
XRD 측정결과 반응 전에는 Ca(OH)2의 피크가 주를 이루고 있으나, 반응 후에는 Ca(OH)2의 피크는 확인할 수 없었으며, CaCO3의 동질이상인 Calcite와 Aragonite 피크만 확인할 수 있었다. As a result of the XRD measurement, the peak of Ca(OH) 2 was dominant before the reaction, but the peak of Ca(OH) 2 could not be confirmed after the reaction, and only the peaks of calcite and aragonite, which are heterogeneous of CaCO 3 , could be confirmed.
TG-DTA 측정결과에서도 반응 전에는 Ca(OH)2의 중량감소만 확인이 되었으나, 반응 후에는 CaCO3의 중량감소만 확인이 되어 완전 탄산화가 이루어진 것으로 판단된다.In the TG-DTA measurement results, only a decrease in the weight of Ca(OH) 2 was confirmed before the reaction, but only a decrease in the weight of CaCO 3 was confirmed after the reaction, indicating that complete carbonation was achieved.
국내 대형 양회사들은 레미콘 사업도 병행하는 경우가 많으므로, 시멘트 공장에서 배출되는 CO2를 포집하거나 바이패스시킴으로써, 시멘트 공장에 인접한 레미콘 공장의 회수수와 연계함으로써, 시멘트 생산시 자제 발생하는 CO2의 다량 고정화가 가능하다. [도 8]은 시멘트 공장 및 레미콘 공장의 연계를 통한 레미콘 회수수를 이용한 포집 CO2 고정화 기술 개념을 도시한 것이다.Since both large domestic companies often carry out the ready-mix concrete business in parallel, CO 2 emitted during cement production is collected or bypassed by collecting or bypassing the CO 2 emitted from cement plants and linking it with recovered water from ready-mix concrete plants adjacent to the cement plant. It is possible to immobilize a large amount of [Figure 8] shows the concept of capture CO 2 immobilization technology using recovered ready-mixed concrete through linkage between a cement plant and a ready-mixed concrete plant.
전국적으로 레미콘 공장은 약 1,080 여개가 운영 중에 있으며, 연간 발생하는 레미콘 회수수의 양은 하루 평균 12만톤 이상으로 추정되고 있다. 따라서 전국 각지에서 포집된 CO2를 거점 인근 레미콘 공장으로 이송하여 초임계 CO2의 급속 탄산화를 통한 CO2 고정화가 이루어진다면 시멘트 산업 뿐만 아니라 전 산업에서 발생되는 CO2의 활용이 가능할 것으로 보인다([도 9] 참조). There are approximately 1,080 ready-mixed concrete plants in operation nationwide, and the amount of ready-mixed concrete recovered annually is estimated to be more than 120,000 tons per day on average. Therefore, if CO 2 collected from all over the country is transported to a ready-mix concrete plant near the base and CO 2 is immobilized through rapid carbonation of supercritical CO 2 , it seems possible to utilize CO 2 generated not only in the cement industry but also in all industries ([ 9]).
본 발명은 위에서 언급한 바와 같이 시험예와 관련하여 설명되었으나, 본 발명의 요지를 벗어남이 없는 범위 내에서 다양한 수정 및 변형이 가능하며, 다양한 분야에서 사용 가능하다. 따라서 본 발명의 청구범위는 이전 발명의 진정한 범위 내에 속하는 수정 및 변형을 포함한다.Although the present invention has been described in relation to test examples as mentioned above, various modifications and variations are possible without departing from the gist of the present invention, and can be used in various fields. Accordingly, the scope of the present invention includes modifications and variations falling within the true scope of the foregoing invention.
10 : 반응기 11 : 가열판 12 : 열전대
13 : 압력게이지 14 : 드레인 15 : 커버
20 : 교반기 21 : 교반날개 22 : 모터
30 : 봄베 40 : 가스부스터 50 : 에어컴프레셔10: reactor 11: heating plate 12: thermocouple
13: pressure gauge 14: drain 15: cover
20: stirrer 21: stirring blade 22: motor
30: Bomb 40: Gas booster 50: Air compressor
Claims (7)
상기 레미콘 회수수는 고형분 함량이 5~25 wt%이고, 상기 고형분은 XRF 분석 시 CaO 성분이 30 wt% 이상 포함되어 있으며,
상기 레미콘 회수수가 수용된 밀폐된 반응기(Reactor)에 초임계 CO2가 주입되고, 상기 반응기 내부는 온도 35~80℃, 압력 75~160 bar가 유지되면서, 상기 반응기 내부 중앙에서 100~400 rpm으로 축회전 하는 교반기(Agitator)의 5~30분 구동에 의해 상기 레미콘 회수수와 초임계 CO2가 교반되며 급속 탄산화 반응이 이루어져 상기 레미콘 회수수 고형분의 완전 탄산화가 이루어지도록 하는, 레미콘 회수수로 CO2를 고정하는 방법.
A method of injecting the collected CO 2 into the ready-mixed concrete recovered water in a supercritical state, so that CaCO 3 is generated by a rapid carbonation reaction of Ca(OH) 2 in the ready-mixed concrete recovered water by supercritical CO 2 ,
The ready-mixed concrete recovery water has a solid content of 5 to 25 wt%, and the solid content contains more than 30 wt% of CaO when analyzed by XRF,
Supercritical CO 2 is injected into a sealed reactor containing the ready-mixed concrete recovery water, and the inside of the reactor is maintained at a temperature of 35 to 80 ℃ and a pressure of 75 to 160 bar, and the axis is rotated at 100 to 400 rpm at the center of the reactor. By driving a rotating agitator for 5 to 30 minutes, the ready-mixed concrete recovered water and supercritical CO 2 are stirred and a rapid carbonation reaction occurs to ensure complete carbonation of the solid content of the ready-mixed concrete recovered water. CO 2 is used as ready-mixed concrete recovered water. How to fix it.
상기 레미콘 회수수는 상기 급속 탄산화 반응 전·후에 pH가 12 이상에서 9.0~9.5로 낮아지는 것을 특징으로 하는, 레미콘 회수수로 CO2를 고정하는 방법.
In paragraph 1:
The ready-mixed concrete recovered water is characterized in that the pH is lowered from 12 or more to 9.0 to 9.5 before and after the rapid carbonation reaction. A method of fixing CO 2 with ready-mixed concrete recovered water.
포집된 CO2가 봄베(Bombe)에 저장되었다가 가스부스터(Gas Booster)를 거쳐 초임계 상태로, 상기 반응기(Reactor)에 주입되는 것을 특징으로 하는, 레미콘 회수수로 CO2를 고정하는 방법.In paragraph 1:
A method of fixing CO 2 with recovered ready-mixed concrete, characterized in that the collected CO 2 is stored in a bomb and then injected into the reactor in a supercritical state through a gas booster.
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