セメント系材料の炭素吸収ダイナミクス:市場構造、材料使用、炭素循環の連携
Hessam AzariJafari1, Ipek Bensu Manav1, Motahareh Rahimi1
1Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139.
まとめ
セメント製品は、ライフサイクル中に大気中の二酸化炭素(CO2)を吸収します。この研究では、米国とメキシコでの炭素吸収量を定量化し、2024年のセメント排出量の13%を相殺する可能性があることを発見しました。
科学分野:
- 環境科学
- 材料科学
- 地球化学
背景:
- セメント系製品は、世界の炭素循環において重要な役割を果たしています。
- セメントによる炭素隔離は、その用途と地域的要因の影響を受けます。
- セメントのライフサイクル全体を通じた炭素影響を理解することは、気候戦略にとって不可欠です。
研究 の 目的:
- 米国とメキシコにおける様々な最終用途におけるセメント系製品の炭素吸収量を定量化すること。
- セメントにおける炭素隔離の地域差と影響要因を分析すること。
- 建設セクターのカーボンニュートラル戦略としてのセメント炭素吸収の可能性を評価すること。
主な方法:
- セメントの最終用途(建物、舗装、橋、パイプライン、インフラ)のためのボトムアップモデルの実装。
- セメント材料の使用中および使用終了時の炭素吸収量の推定。
- 建物の種類、コンクリート配合設計、気候変動に関する地域データの分析。
主要な成果:
- 2024年には、炭素吸収によりセメント製造工程からの排出量の約13%(6.7 Mt CO2)を隔離できる可能性があります。
- 地域差により、州ごとに面積あたりの吸収量に4倍のばらつきが見られました。
- 建築分野は、インフラシステムと比較して約2倍の炭素吸収を示しています。
- メキシコでは、既存のセメント製品が、産業界の年間製造排出量の約4分の1を隔離しています。
結論:
- セメント系製品の炭素吸収は、地域的な文脈によって大きく異なる重要な要因です。
- セメントの炭素吸収を強化することは、建設セクターのカーボンニュートラル目標のための実行可能な戦略を提供します。
- これらの発見は、人為的な材料が炭素循環計算と国の温室効果ガスインベントリにどのように影響するかを再評価する必要があることを示唆しています。
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