Chestnutt Thomas E, Bach Morgana T, Mazyck David W
Department of Environmental Engineering Sciences, The University of Florida, 306 AP Black Hall, P.O. Box 116450, Gainesville, FL 32611, USA.
Water Res. 2007 Jan;41(1):79-86. doi: 10.1016/j.watres.2006.09.010. Epub 2006 Nov 13.
Rapid small-scale column tests (RSSCTs) were employed to evaluate the impact of the dissolved oxygen (DO) concentration in the water used to create steam on the reactivation of spent granular activated carbon (GAC) using three novel thermal reactivation procedures: steam-curing, steam-curing with ramped temperature, and steam pyrolysis reactivation. Evaluation of the physical properties of the reactivated carbon showed a change in mass and volume loss with a change in DO. Performance testing of the carbons for removal of the taste- and odor-causing compound 2-methylisoborneol (MIB) showed that MIB uptake generally increased as the DO concentration decreased. Decrease in MIB removal with an increase in surface acidity, a phenomenon found in the literature, may be responsible for the changes in adsorption performance, as the higher DO concentrations yielded carbons with higher total surface acidity. In addition, the steam-curing process, which was implemented at 375 degrees C (i.e. about 400 degrees C lower than typical reactivation temperatures) with a low DO concentration (i.e. 3-4mg/L) had comparable performance to the virgin carbon counterpart, which could manifest cost-savings due to the low temperature associated with this protocol compared to conventional reactivation. Furthermore, since the mass loss associated with this steam-curing protocol was low, less virgin carbon make-up would be required also improving the economic viability of this reactivation protocol.
采用快速小规模柱试验（RSSCTs），利用三种新型热再生程序——蒸汽养护、变温蒸汽养护和蒸汽热解再生，评估用于产生蒸汽的水中溶解氧（DO）浓度对废颗粒活性炭（GAC）再生的影响。对再生碳物理性质的评估表明，质量和体积损失随溶解氧的变化而变化。对去除引起味道和气味的化合物2-甲基异冰片（MIB）的碳进行性能测试表明，随着溶解氧浓度的降低，MIB的吸附量通常会增加。文献中发现，随着表面酸度的增加，MIB去除率降低，这一现象可能是吸附性能变化的原因，因为较高的溶解氧浓度会产生具有较高总表面酸度的碳。此外，在375℃（即比典型再生温度低约400℃）和低溶解氧浓度（即3-4mg/L）下实施的蒸汽养护工艺与原始碳具有相当的性能，与传统再生相比，由于该工艺温度较低，可能会节省成本。此外，由于与该蒸汽养护工艺相关的质量损失较低，所需的原始碳补充量也较少，这也提高了该再生工艺的经济可行性。
