A two-dimensional simulated sand box was used to investigate the remediation efficiency of naphthalene contaminated groundwater by Tween80-enhanced groundwater circulation well (GCW). The mobility characteristic of Tween80 in groundwater, the hydraulic control of Tween80 by GCW during the remediation process, the solubilization of naphthalene as well as the enhanced remediation effect were all studied. The results show that the vertical mobility rate of Tween80 is higher than that in longitudinal direction after adding Tween80 to ground water. The mobility of Tween80 can be controlled by GCW perfectly. And Tween80 flows to GCW gradually in the process of GCW. Solubilization of naphthalene by Tween80 is obvious 24 h after Tween80 is added. The average mass concentration of naphthalene in simulate slot increases from 1.82 mg/L to 3.62 mg/L. The solubilized naphthalene is carried to GCW by groundwater after starting the remediation of circulation well. A cone-shaped remediation area is gradually formed around GCW and naphthalene can be removed by aeration. The mass concentration of naphthalene goes through the two stages of rapid decline and slow decline. In the first 2 h of efficient remediation time in the aeration, the average mass concentration of naphthalene decreases fast to 1.98 mg/L followed by a slow decline, and the trailing concentration is 0.69 mg/L.%利用二维模拟槽实验研究Tween80增溶作用对地下水循环井技术(GCW)修复萘的强化效果。分析Tween80在地下水中的迁移特性、强化修复过程中地下水循环井对Tween80的水力控制作用、Tween80对萘的增溶效果及最终强化修复效果。研究结果表明：Tween80注入地下水后，其垂向迁移距离明显大于横向迁移距离；地下水循环井能够对Tween80进行有效的水力控制，将其控制在循环井周围；Tween80注入24 h后，模拟槽内萘的质量浓度普遍上升，平均质量浓度由1.82 mg/L上升至3.62 mg/L；启动循环井修复后，增溶至水中的萘在水流作用下不断迁移流向循环井，并通过曝气吹脱去除，最终在循环井附近形成一个高效修复区域。萘的质量浓度经历快速下降−缓慢下降的修复过程，高效修复时间集中在曝气的前2 h内，地下水中萘的平均质量浓度降至1.98 mg/L，之后进入缓慢下降阶段，萘的拖尾质量浓度为0.69 mg/L。
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