原位修复是地下水污染修复的研究热点，地下水循环井技术是一种地下水原位修复技术，因其具有效率高、对环境扰动小、易于与曝气、吹脱、生物强化和化学氧化等其它处理技术相结合等特点，在很多场地条件下具有独特的优势。地下水污染修复实践在我国起步较晚，有关地下水循环井技术的相关研究还很少，更鲜有工程应用的案例。因此，有必要对地下水循环井技术进行研究，明确循环井的适用条件以指导循环井系统的设计与应用。

本文针对具有两个筛管的循环井进行理论分析，探讨了地下水循环半径的影响因素以及设计与优化等方面的评价指标。通过构建地下水流模型，刻画了地下水循环井的三维循环流径，分析单因素变化对地下水循环井的影响半径、循环周期的影响，以某石油烃污染场地为研究案例，建立不同的情景模式及运行工况，模拟了不同模式的循环井对污染场地地下水的治理效果，为实际工程应用提供参考依据。

论文取得的主要认识如下：

（1）分析现有地下水循环井的理论，确定了循环井修复效率影响因素，包括污染物性质、场地水文地质条件，以及地下水循环井设计参数条件。

（2）模拟了多组不同环流模式、抽注流量、抽注段长度、间距及不同水文地质参数条件，绘制稳态降深图、地下水流场图、影响半径规律图，通过对比分析，论证了单因素变化对循环井循环影响半径的影响。

（3）提出无量纲参数，定量分析了单因素变化对循环井循环影响半径的影响，建立了相关的单因素变化对循环半径的影响公式。

（4）利用粒子跟踪方法建立了回收率指标，包括粒子从注入段到抽取段的移动时间或给定时间后的回收率，阐明了环流模式、抽注段筛管长度、筛管间距、各向异性、水力梯度对回收率的不同影响。

（5）以某石油烃污染场地为例，设置不同的循环井修复情形，模拟了不同工况的修复效果，为工程应用提供了指导。

In situ remediation is a research hotspot of groundwater pollution remediation technology, the groundwater circulation well (GCW) technology belongs to in-situ remediation technology, GCW is of unique advantages with the characteristic of high efficiency, easy to combine with aeration, bioaugmentation, chemical oxidation and other treatment technologies, has been successfully applied to contaminated sites. In China, seldom researches reported groundwater circulation well technology, engineering application cases are even rare. Therefore, it is necessary to study the theory and technology of GCW, clarify its applicable and guidance.

This thesis aims at theoretical analysis for the circulation well with two screens, discussing the influence factors of circulation well radius, and evaluating the indexes of system design and optimization. We constructed a groundwater flow model, described the three-dimensional circulation flow path of GCW, and analyzed the influence of single factor change on the radius and cycle of GCW. On the basis of the data of a petroleum hydrocarbon contaminated site, different scenarios and operation conditions were established to simulate the treatment effect of different modes of circulating wells on groundwater in the contaminated site, so as to provide reference for practical engineering application.

The thesis has mainly obtained the following understandings:

(1) Analyzed existing theory of GCW, determined the influencing factors of GCW remediation efficiency, which includes the pollutants nature, hydrogeological conditions of the site, and design parameter conditions.

(2) Simulated several groups of different circulation models, pumping and injection flow, length of pumping section and spacing and different hydrogeological parameters. Drews groundwater flow field map and influence radius diagram. Through comparative analysis, the influence of single factor change on circulation influence radius of GCW is demonstrated.

(3) Introduced dimensionless parameters, further quantitatively analyze the influence of single factor change on circulation radius, and established the formula of the influence of single factor change on the circle radius.

(4) Particle tracking method was used to establish recovery index, including the moving time of particles from the injection section to the extraction section or the recovery rate after a given time. Clarifies the effects of circulation model, length of pumping and injection screen, spacing of screen, anisotropy and hydraulic gradient on the recovery rate.

(5) Taking a petroleum hydrocarbon contaminated site as an example, we set up different recycling wells to simulate the remediation effect under different conditions, so as to provide reference for engineering application.