Mild Conductive Thin Film Drying: Energy Efficiency & Product Quality Cluster: Drying and dewatering (DR-20-03) Project Leader: Maarten Schutyser (WUR) Researcher: Jun Qiu (WUR) Partners: ISPT, WUR, Bodec, ECN, ILVO, Unilever Project duration: February 2015 – March 2019 Motivation: Conductive thin film drying processes consume ~40% less energy than spray drying. However, these conductive drying processes yield different powder properties. In this project we investigate the principles of conductive film drying at lab and pilot scale to improve powder functionality and energy efficiency. Experimental set-up: Vacuum Thin Film Dryer (DryVaGram) This custom built experimental setup is used to mimic and thus study (vacuum) drum drying (Figure 1). Mass and temperature changes during drying are monitored in-line (Figure 2). Objective: To establish mechanistic insight on film drying behaviour via lab-scale experimentation and development of transient drying models. Systematic comparison of pilot-scale film dryers to develop knowledge-based guidelines for (vacuum) drum drying and ATFD drying. Experimental setup: Agitated Thin Film Dryer (ATFD) This lab-scale ATFD dryer is built to investigate agitated thin film drying. (Figure 3). The ATFD drying mechanism based on new experiments is presented in Figure 4. Figure 3. Equipment of ATFD set-up Figure 1. Equipment of the vacuum thin film drying set-up Sample products Inlet hot water Outlet hot water Vapour + Vacuum Blades Heating jacket Stage 1: Liquid Bow wave growth Stage 2: Paste Lump accumulation Stage 3: Solid Powder formation Drying chamber Powder collector Figure 4. Schematic representation of ATFD drying. Figure 2. Mass (left) and temperature (right) during evaporation of a 1 mm thick film of water with the DryVaGram. This project is co-funded by TKI-E&I with the supplementary grant 'TKI- Toeslag' for Topconsortia for Knowledge and Innovation (TKI’s) of the Ministry of Economic Affairs and Climate Policy.