Increasing energy saving of pilot-scale spray dryers with enhanced yield by low-adhesive surfaces

Abstract

Spray drying process, widely used in industrial applications, is highly energy-consuming. To reduce the energy consumption under the secured yield, optimizing the operating conditions of drying process or utilizing heat from the exhaust air of dryers has been carried out. Albeit their successful demonstration of energy saving, securing the yield of drying process still requires high temperature processing. Since high temperature processing often degrades or denatures the quality of dried materials in specific applications, further development of diverse strategies is necessitated for yield enhancement in low temperature environments. Herein, a spray drying method with low-adhesive surfaces is proposed to considerably increase the yield of drying process with no additional energy consumption or devices to accomplish the equivalent effects of the enhanced energy saving of spray dryers under the identical operating condition. The experimental results reveal that due to the significant reduction of the particle accumulations in the chamber of the spray dryer, equipping the low-adhesive surfaces to the conical walls of the pilot-scale spray dryer achieves up to 16.5% higher yield than control surfaces under identical operating conditions. This brings about the enhanced energy saving up to 14.2% to acquire the identical powder collection by the spray drying process.