鉄鋼スラグのCO2固定量定量における方法論的差異の批判的評価

Unofficial AI-generated summary based on the public title and abstract. Not an official translation.

🔬研究者:炭素固定測定の手法間バイアスと証拠チェーン設計を理解するための方法論的基盤を提供する。

🏢実務担当者:スラグ炭酸化やCCUSの炭素除去量を開示・検証する際、採用手法と不確実性の明示が求められる点を実務に反映できる。

🏛政策担当者:炭素除去・CCUSの認証制度設計において、測定手法の標準化と不確実性報告要件の必要性を示唆する。

Steel slag, rich in free CaO/MgO, calcium silicates, and calcium ferrites, suits engineering, boosting alkaline solid waste and carbonating CO2 minerals. However, studies interpret CO2 sequestration capacity differently. Metrics like CO2 sequestration capacity, mass gain, and carbonate content are lumped as capture measures, blocking cross-study comparison and inconsistent carbonation assessments. The study rigorously evaluates seven conventional measurement techniques: thermogravimetric analysis, mass gain measurement, gas consumption monitoring, acid digestion method, elemental analysis, combustion-infrared absorption spectrometry, and X-ray diffraction, thoroughly discussing their quantifiable targets, relevant scopes, systematic biases, and failure scenarios. Representative data show 7-day CO2 sequestration values of 6.5–10.2 g CO2/100 g initial sample across four analytical routes; stepwise-TG, tangential-TG, combustion-infrared AD-TIC, and acid-digestion HT-TIC gave 9.0, 6.5, 10.2, and 9.7 g CO2/100 g, respectively, corresponding to a highest-to-lowest spread of 3.7 g CO2/100 g (36.3% of the highest value). Analytical findings indicate that variances among testing techniques arise not only from arbitrary measurement errors but mainly from differences in specific carbon pools, protocols for sample pre-treatment, criteria for identifying carbonate species, categorization of gas–liquid–solid phase limits, and methods for assessing statistical uncertainty. Consequently, this document suggests a quadruple-tiered evidence chain structure, encompassing the material background, process mass equilibrium, product-associated carbon measurement, and statistical fusion layers. An array of functional standards has been formulated, encompassing the removal of background baselines, confirmation of mass closure, four-point cross-validation, and broadened reporting of uncertainties. The suggested model converts the measurement of steel slag’s carbon capture ability from isolated, singular measurements to a system that is traceable, confirmable, and verifiable with multiple evidence sources. This offers strong methodological backing for large-scale lab experiments, expanding processes, confirming carbon emission reductions, and developing uniform testing procedures. To improve operational clarity, the framework explicitly distinguishes background solid inorganic carbon, newly mineralized stable solid carbon, liquid-phase dissolved inorganic carbon, physically retained CO2, and crystalline carbonate carbon; it also introduces quantitative decision bands for mass closure and cross-method agreement and demonstrates reconciliation using a published multi-method BOF steel-slag dataset.

• semanticscholar https://doi.org/10.3390/ma19194032first seen 2026-09-26 05:02:07 · last seen 2026-09-28 05:43:20