Tohoku University · Environmental Science
이 교수의 연구실은 폐기물 기반 자원 회수와 탄소 포집·이용 기술을 핵심으로 하는 지속가능한 자원 순환 기반 기술을 개발하고 있습니다. 주로 폐세라믹, 폐콘크리트 슬러지 등 건설 폐기물을 원료로 삼아 고순도 칼슘탄산염과 인 회수용 흡착제를 생산하는 공정 기술을 연구하고 있으며, 이 과정을 통해 탄소 배출을 줄이고 자원 순환을 실현합니다. 특히, CO₂를 활용한 미네랄 탄소포집 및 활용(MCC&U) 기술의 실증과 응용을 통해 건설 산업의 탄소중립화에 기여하고자 합니다.
Figures are computed from collected data and may differ slightly.
We propose a new sequestration process for anthropogenic carbon dioxide (CO2) that uses waste cement. The proposed process consists of two main reactions. The first is the extraction of calcium ions (Ca2+) from waste cement particles by pressurized carbon dioxide (several megapascals of pressure). The second is the precipitation of calcium carbonate (CaCO3). Ca2+ extracted from waste cement is deposited as CaCO3 when the pressure is reduced. CaCO3 is disposed of directly, or recycled as a raw ma
Cement is widely produced and used. Cement production consumes a significant amount of energy and natural resources, and it accounts for approximately 7% of man-made greenhouse gas (GHG) emissions in CO2-equivalents globally. The cement industry is continually conducting research and development into energy conserving and low-carbon technologies to reduce CO2 emissions. Furthermore, the industry will be at the heart of a carbon recycling system along cement and concrete value chain using newly d
Abstract A new type of process for producing high‐purity calcium carbonate from waste cement powder was developed. The process consists of two main reactions; extraction of calcium in the form of calcium ions from waste cement powder in a water slurry by pressurized CO 2 (typically at several MPa), and precipitation of calcium carbonate (CaCO 3 ) from the extracted solution by reduction of the CO 2 pressure. The process can be recognized as the emission reduction process of CO 2 as well. Laborat
A bench-scale plant for waste concrete sludge recycling was designed, constructed, and operated. Real concrete sludge generated from a pile and pole production plant and groundwater were used for the experiments. The process mainly consists of the extraction of calcium ions from the concrete sludge into the aqueous phase and the crystallization of calcium carbonate from the solution with CO2. The CO2 was supplied from boilers installed in the plant, where heavy oil is combusted. High-purity calc
A pilot-scale plant to treat concrete sludge and produce calcium carbonate (CaCO3) and an environmental purification agent (phosphorus adsorbent derived from concrete sludge, PAdeCS®) was designed, constructed, and operated. Concrete sludge from a concrete pile and pole production plant, boiler gas containing CO2, and groundwater were used in the plant. The process involved calcium extraction from concrete sludge into water, followed by reaction of the calcium with CO2 to produce crystalline CaC
Solid adsorbents for phosphorus recovery (PAdeCS) were prepared from real concrete sludge sampled from an industrial site that produces concrete poles and piles. The concrete sludge was diluted with water at dilution ratios from 1 to 15 to prevent hardening of the cement components. The diluted concrete sludge was then filtered, dried, and used as a solid adsorbent. Two drying methods were examined: natural drying under atmospheric conditions and forced drying in an oven at 105 °C. The phosphoru
Low-cost materials for boron removal need to be developed to reduce the overall cost of treatment of boron-containing wastewater. In this paper, the preparation of a boron removal material using waste concrete particles is described. With high initial boron concentrations (100 and 300 mg/L boron), the removal performance was insufficient and the dominant boron removal mechanism was estimated to be precipitation of calcium borate. With a low initial boron concentration (10 mg/L boron), more boron
This study demonstrates an application of cluster analysis to constant ambient air monitoring data of four pollutants in the Kanto region: NOx, photochemical oxidant (Ox), suspended particulate matter, and non-methane hydrocarbons. Constant ambient air monitoring can provide important information about the surrounding atmospheric pollution. However, at the same time, ambient air monitoring can place a significant financial burden on some autonomous communities. Thus, it has been necessary to red
コンクリートスラッジ中のカルシウムを利用した二酸化炭素固定プロセスを想定し，そのための基礎データ取得を行った．想定するコンクリートスラッジを利用した二酸化炭素固定プロセスの主要操作は，水希釈と撹拌によるコンクリートスラッジ中のカルシウム分の抽出過程と，残渣分離後の抽出水と二酸化炭素との反応による炭酸カルシウム析出過程である．想定するプロセスの基礎データの取得を目的として，コンクリートポール／パイル工場から排出された実際のコンクリートスラッジを用い，カルシウム抽出速度に対する水希釈率（重量比で3–50倍）と一回の抽出操作時間（5–40 min）の影響を検討した．水希釈後水中のカルシウム濃度は上昇し，抽出液中に二酸化炭素を吹き込むことで炭酸カルシウムの析出が行えることを確認した．実験を行った範囲では，水稀釈率が20，一回の抽出処理時間が5 minの場合にカルシウム抽出効率が最大となった．二酸化炭素とカルシウム含有溶液からの炭酸カルシウム生成は，これまでに多くの研究例があり，また種結晶などの追加による加速が容易である．以上から，二酸化炭素固定のための安価なカルシウム源としてコンクリートスラッ
Experimental study was conducted on the simultaneous process of decomposition and fixation of fluoride of F-gases. HFC-134a, a hydrofluorocarbon (HFC), used most widely, was selected as a model gas, and its decomposition performances were examined in a tube type reactor with and without waste concrete powder. Decomposition of HFC-134a was observed at temperatures above 500 °C, while no thermal decomposition occurred below 750 °C without waste concrete. The results for the differential type react
Open papers in the app to read, cite, and organize with AI.
