Tim Hülsen studied water science at the University Duisburg-Essen (Germany) and finalised his study with a Master degree. Afterwards, he worked as a technologist for Paques bv, in The Netherlands. At Paques bv, he was responsible for the design of different anaerobic removal technologies. He was the technology expert for the realisation of several full-scale installations in several countries. Additionally, he became phosphate-removal and anammox technologist at the company. As such, he was the product market development leader, combining laboratory research with full-scale experience to optimise the technologies. These tasks included the industrial as well as the municipal market. During his Ph.D. he focused on simultaneous, non-destructive COD, N and P removal from wastewater, applying purple phototrophic bacteria to enable complete recovery, which is also the main focus of his work as a postdoctoral research fellow.