Cha Woosuk, Kim Jungwoo, Choi Heechul
Department of Civil and Environmental Engineering, Arizona State University, PO Box 875306, Tempe, AZ 85287-5306, USA.
Water Res. 2006 Mar;40(5):1034-42. doi: 10.1016/j.watres.2005.12.039.
Basic oxygen furnace slag (BOFS) was evaluated as an additive to the soil aquifer treatment (SAT) in the laboratory column tests and the characteristic behaviors of organics and inorganic compounds through the columns were examined with both natural soil and the mixture of soil and slag. It was obvious that the slag could contribute more removals of DOC under both unsaturated and saturated conditions of SAT operation possibly due to its larger surface area. The molecular weight fractions of less than 1 kDa was greatly degraded during the unsaturated SAT operation by biodegradation and the molecular weight fractions of higher than 10 kDa was also significantly reduced after unsaturated SAT by adsorption. It was indicated that the steel slag seemed to play an effective role in reducing the refractory organics during saturated SAT. The macroporous XAD resin isolations showed the increase of hydrophilic fractions with a decrease in the hydrophobic and transphilic fractions through SAT. The use of steel slag resulted in adverse effect on the nitrification due to high pH (about 11) and the relative redox potential measurement showed that the steel slag provided a non-oxidative environment in SAT columns. Almost complete removal of phosphate was achieved during unsaturated and saturated SAT operations with a relatively low hydraulic loading rate and effective adsorption by steel slag. A 20-30% increase of sulfate was observed in slag-containing unsaturated columns whereas the saturated 100% slag columns exhibited 68% decrease of sulfate concentration.
在实验室柱试验中，对碱性氧气转炉渣（BOFS）作为土壤含水层处理（SAT）添加剂进行了评估，并通过天然土壤以及土壤与炉渣混合物填充的柱体，研究了有机物和无机化合物的特性行为。很明显，由于炉渣具有较大的表面积，在SAT运行的不饱和和饱和条件下，它都能促进溶解性有机碳（DOC）的更多去除。在不饱和SAT运行期间，分子量小于1 kDa的部分通过生物降解被大量降解，而分子量高于10 kDa的部分在不饱和SAT后也因吸附而显著减少。结果表明，钢渣在饱和SAT过程中似乎对减少难降解有机物起到了有效作用。大孔XAD树脂分离显示，通过SAT，亲水部分增加，疏水和亲脂部分减少。由于高pH值（约11），钢渣的使用对硝化作用产生了不利影响，相对氧化还原电位测量表明，钢渣在SAT柱中提供了一个非氧化环境。在不饱和和饱和SAT运行期间，以相对较低的水力负荷率和钢渣的有效吸附几乎实现了磷酸盐的完全去除。在含渣不饱和柱中观察到硫酸盐增加了20 - 30%，而饱和的100%渣柱中硫酸盐浓度降低了68%。
