The effects of the injection parameters on delivery of nanoscale zero-valent iron (NZVI) to contaminated groundwater were investigated. The first two NZVI injections (gravity injection at low flow rates) resulted in NZVI being poorly mobile and gave total cumulative mass recoveries at the monitoring wells of 1.07%–2.43%. NZVI reached some wells (KDMW-3, MW-2, MW-4, and MW-7) earlier than the bromide tracer. The dominant travel directions for NZVI and the bromide tracer were very different. The NZVI transport characteristics suggested that targeted NZVI delivery requires preferential groundwater flow paths and local heterogeneity to be considered. In the gravity injection tests, the maximum NZVI concentrations and cumulative NZVI mass recoveries in the wells decreased markedly as the injected NZVI concentration and dose increased. In the third and fourth tests, in which NZVI was injected under pressure at high flow rates, NZVI was effectively delivered to the wells despite the injected NZVI concentration and dose being high. Relatively high cumulative mass recoveries of 26.0% and 74.5% were found for the third and fourth injections, respectively. Controlling the flow rate (pressure) and NZVI concentration and dose simply and effectively controlled NZVI mobility in the groundwater. The colloidal and electrostatic characteristics of the NZVI particles were monitored and modeled, and the results indicated that NZVI particles without Derjaguin–Landau–Verwey–Overbeek energy barriers were successfully delivered to the target zone and that decreased magnetic attractive forces between NZVI particles caused by iron corrosion probably decreased the degree of NZVI particle aggregation and therefore contributed to NZVI being delivered to the target zone.

研究了注入参数对向受污染地下水输送纳米级零价铁 (NZVI) 的影响。前两次 NZVI 注入（低流速下的重力注入）导致 NZVI 流动性差，监测井的总累积质量回收率为 1.07%–2.43%。NZVI 比溴化物示踪剂更早到达一些井（KDMW-3、MW-2、MW-4 和 MW-7）。NZVI 和溴化物示踪剂的主要行进方向非常不同。NZVI 运输特征表明，有针对性的 NZVI 输送需要考虑优先的地下水流动路径和当地的异质性。在重力注入试验中，随着注入的 NZVI 浓度和剂量的增加，井中最大 NZVI 浓度和累积 NZVI 质量回收率显着降低。在第三和第四次测试中，NZVI 在压力下以高流速注入，尽管注入的 NZVI 浓度和剂量很高，但 NZVI 仍能有效地输送到井中。第三次和第四次进样的累积质量回收率分别为 26.0% 和 74.5%。控制流速（压力）和 NZVI 浓度和剂量可以简单有效地控制 NZVI 在地下水中的流动性。NZVI 颗粒的胶体和静电特性被监测和建模，