Laboratory of Environmental Engineering, Department of Civil Engineering and Computer Science Engineering, University of Rome "Tor Vergata", Via del Politecnico 1, 00133 Rome, Italy.
Department of Civil and Environmental Engineering, University of Rome "La Sapienza", Via Eudossiana 18, 00184 Rome, Italy.
J Hazard Mater. 2015;283:302-13. doi: 10.1016/j.jhazmat.2014.09.016. Epub 2014 Sep 19.
The results of direct aqueous accelerated carbonation of three types of steel manufacturing residues, including an electric arc furnace (EAF) slag and two basic oxygen furnace (BOF) slags, are reported. Batch accelerated carbonation tests were conducted at different temperatures and CO2 pressures applying the thin-film route (liquid to solid, L/S, ratio=0.3L/kg) or the slurry-phase route (L/S ratio=5L/kg). The CO2 uptake strongly depended on both the slag characteristics and the process route; maximum yields of 280 (EAF), 325 (BOF1) and 403 (BOF2) gCO2/kg slag were achieved in slurry phase at T=100°C and pCO2=10 bar. Differently from previous studies, additional carbonates (other than Ca-based phases) were retrieved in the carbonated BOF slags, indicating that also Mg-, Fe- and Mn-containing phases partially reacted with CO2 under the tested conditions. The results hence show that the effects of accelerated carbonation in terms of CO2 uptake capacity, yield of mineral conversion into carbonates and mineralogy of the treated product, strongly rely on several factors. These include, above all, the mineralogy of the original material and the operating conditions adopted, which thus need specific case-by-case optimization to maximize the CO2 sequestration yield.
报告了三种钢铁制造渣（包括电弧炉渣和两种碱性氧气炉渣）直接水加速碳酸化的结果。采用薄膜法（液固比，L/S，=0.3L/kg）或浆相法（L/S 比=5L/kg）在不同温度和 CO2 压力下进行了批量加速碳酸化试验。CO2 吸收强烈取决于渣的特性和工艺路线；在 T=100°C 和 pCO2=10 bar 时，浆相法可分别获得 280（EAF）、325（BOF1）和 403（BOF2）gCO2/kg 渣的最大产率。与以前的研究不同，在碳酸化的 BOF 渣中还回收了其他碳酸盐（除 Ca 基相之外），这表明在测试条件下，含 Mg、Fe 和 Mn 的相也与 CO2 部分反应。因此，结果表明，加速碳酸化在 CO2 吸收能力、矿物转化为碳酸盐的产率和处理产物的矿物学方面的效果强烈依赖于几个因素。这些因素包括但不限于原始材料的矿物学和采用的操作条件，因此需要具体情况具体优化，以最大限度地提高 CO2 固存产量。
