Transport characteristics of emulsified nanoscale-zero-valent-iron in saturated porous media
DONG Jun1, LI Chang-suo1, WEN Chun-yu2, HAN Jian-jiang2
1. Shandong Provincial Geo-mineral Engineering Exploration Institute, Jinan 250000; 2. College of Environment and resources, Jilin University, Changchun, Jilin, 130021
Abstract：The scope of this research is to investigate the transport characteristics and influencing factors of remedial agent-emulsified nanoscale-zero-valent-iron (EZVI). One-dimensional column experiments were conducted to obtain breakthrough curves and substrate distribution of EZVI, and results indicated that:the modification of NZVI by emulsified oil improved the transportability of NZVI, and the migration distance of EZVI was 2~3 times increased compared with that of NZVI. The excess of emulsified oil in EZVI suspension transported down-gradient with groundwater flow, forming two reaction zones with NZVI and emulsified oil, respectively. Larger size of the sand grain facilitated the transport of EZVI, and the migration distance in coarse sand was about 1.9 times longer than that in the fine sand. The injection velocity affected the transport by controlling single collector efficiency, and higher collection probability was achieved by higher injection velocity. The co-existing ions have little effect on the EZVI transport ability. When the injection velocity of EZVI was 3cm/min, and the slurry concentration was 2g/L, the transport showed best performance.
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