Heat-Pump-Assisted Drying: Recent Technological Advances and R&D Needs

Drying is one of the most energy-intensive processes in many industries. Among other technologies, drying heat pumps help to reduce primary energy consumption as well as greenhouse gas emissions. First, this paper reviews some of the general R&D requirements and challenges for heat pumps in general. Second, based on a brief review of the drying literature and the author's experience, the paper focuses on technical integration and control-required improvements as well as on future R&D needs for drying heat pumps. It suggests more rigorous studies and increased interaction between drying, heat pump, and process control researchers and specialists at both the academia and industry levels. The main goal is to stimulate the successful application of drying heat pumps in various industrial fields.