Recovery and treatment of cooling tower blowdown water: challenges, recent advancement, and future perspectives

The imperative nature of wastewater treatment stems from escalating concerns regarding water scarcity, public health, and environmental conservation. Recognizing wastewater as a valuable resource hinges on the advancement of sustainable technologies. Specifically, the treatment of cooling tower blowdown water (CTBW) from diverse industrial and district cooling facilities is of paramount importance. Effective CTBW treatment is crucial for both industrial operations and environmental protection. The heterogeneous nature of contaminants present in CTBW necessitates specialized techniques for their comprehensive removal. Therefore, a thorough review of existing treatment technologies and the challenges they face is imperative. This paper presents a comprehensive review of current and emerging water treatment technologies with a focus on improving the treatment of CTBW. It critically assesses the intrinsic characteristics of CTBW to determine its suitability for either direct discharge or conventional treatment methods. The study carefully examines the challenges associated with current technologies, while highlighting recent advances in the sustainable treatment and reuse of CTBW. It also compares existing technologies, examines the integration of complementary pre-treatment methods and considers future prospects for optimizing performance. Ultimately, the study concludes that CTBW can be effectively recycled and recognized as a resource within industrial applications.