Cooling towers are responsible for a large part of the industrial fresh water withdrawal, and the reuse of cooling tower water (CTW) effluents can strongly lower industrial fresh water footprints. CTW requires desalination prior to being reused, but various CTW components, such as total organic carbon (TOC), conditioning chemicals and total suspended solids (TSS) hamper physico-chemical desalination technologies and need to be removed from the CTW. A cost-efficient and robust pre-treatment is thus required, which can be provided by constructed wetlands (CWs). The present study is the first study that determined the CTW pre-treatment efficiency of hybrid-CWs and the impact of winter season and biocides in the CTW on the pre-treatment efficiency. The most efficient CW flow type and dominant removal mechanisms for CW components hampering physico-chemical desalination were determined. Subsurface flow CWs removed PO₄³⁻, TSS and TOC as a result of adsorption and filtration. Vertical subsurface flow CWs (VSSF-CW) excelled in the removal of benzotriazole as a result of aerobic biodegradation. Horizontal subsurface flow CWs (HSSF-CW) allowed the denitrification of NO₃⁻ due to their anaerobic conditions. Open water CWs (OW-CWs) did not contribute to the removal of components that hamper physico-chemical desalination technologies, but do provide water storage options and habitat. The biological removal processes in the different CW flow types were negatively impacted by the winter season, but were not impacted by concentrations of the biocides glutaraldehyde and DBNPA that are relevant in practice.

For optimal pre-treatment, a hybrid-CW, consisting of an initial VSSF-CW followed by an OW-CW and HSSF-CW is recommended. Future research should focus on integrating the hybrid-CW with a desalination technology, e.g. reverse osmosis, electrodialysis or capacitive ionization, to produce water that meets the requirements for use as cooling water and allow the reuse of CTW in the cooling tower itself.

冷却塔是工业淡水抽取的主要部分，而冷却塔水（CTW）废水的再利用可以大大降低工业淡水的足迹。CTW在重新使用之前需要脱盐，但是各种CTW组件，例如总有机碳（TOC），调理化学品和总悬浮固体（TSS）妨碍了物理化学脱盐技术，因此需要从CTW中移除。因此，需要一种经济高效且坚固的预处理，这可以由人工湿地（CW）提供。本研究是第一项确定混合CW的CTW预处理效率以及冬季和CTW中杀菌剂对预处理效率的影响的研究。确定了最有效的CW流动类型和CW组分阻碍物理化学脱盐的主要去除机理。地下流CW已去除PO₄ ^3-，TSS和TOC作为吸附和过滤的结果。由于需氧生物降解，垂直地下流CW（VSSF-CW）在去除苯并三唑方面表现出色。水平潜流的CW（HSSF-CW）允许NO的脱氮₃ ^-由于其厌氧条件。开放水化学废物（OW-CW）并未有助于去除妨碍理化淡化技术的成分，但确实提供了储水选择和栖息地。在不同的连续水流类型中，生物去除过程受到冬季的负面影响，但不受实践中相关的杀生物剂戊二醛和DBNPA浓度的影响。

为了进行最佳的预处理，建议使用混合CW，该混合CW由初始VSSF-CW，OW-CW和HSSF-CW组成。未来的研究应集中在将混合式CW与脱盐技术（例如反渗透，电渗析或电容电离）集成在一起，以生产满足用作冷却水要求的水，并允许CTW在冷却塔本身中重复使用。