**Preface to "Gas, Water and Solid Waste Treatment Technology"**

Environmental pollution, including gas pollution, water pollution, and solid waste pollution, are the main social and environmental problems. A variety of treatment technologies, such as physical, chemical, and biological methods, have been used for the treatment of these pollutants. This book includes 34 review and research works focused on the various techniques, processes, and theories for gas, water and solid waste treatments.

> **Zhien Zhang, Avelino N ´u ˜nez-Delgado, Wenxiang Zhang** *Editors*
