This thesis explores how to improve the drying process for seaweed at Upcyclr AB, a Swedish company dedicated to reducing food waste through sustainable upcycling technologies. Seaweed is increasingly valued as a nutritious and sustainable food source, but its high moisture content requires careful drying to preserve quality and nutrients. Upcyclr AB’s existing system uses a heat pump and tray drying method, but the company sought to further enhance energy efficiency, product quality, and sustainability.

To address these goals, the thesis first analyzes the theoretical background and current operation of the company’s drying system, identifying how heat transfer, airflow, and process controls affect both energy use and seaweed quality. Next, alternative drying methods and technical improvements are evaluated, including solar-assisted heat pumps, microwave-vacuum drying, and adjustments to tray design and airflow. The study also examines how different drying parameters, such as temperature, air velocity, and humidity, impact the retention of vitamins, minerals, and bioactive compounds in seaweed. Notably, the research finds that moderate drying temperatures (50–60°C) and controlled airflow (1.5–2.0 m/s) best preserve sensitive nutrients like vitamin C and polyphenols, while excessive heat leads to significant losses. The integration of infrasound technology is also proposed, as it can be used alongside internal fans to enhance moisture removal and drying efficiency without disrupting existing airflow.

Due to limitations in experimental access, the research is based on literature review, company documentation, and expert interviews. The thesis delivers actionable recommendations for Upcyclr AB, including optimizing drying parameters, adopting advanced or hybrid systems, and implementing real-time monitoring. These improvements are expected to reduce energy use, shorten drying times, and ensure high-quality, nutritious seaweed products. The findings benefit both Upcyclr AB and the broader seaweed industry by supporting more sustainable and efficient food processing.