Spray Drying Specialists Choose Low-Cost Alternative to Rotary Valve: A Vacu-Valve Success Story

“It just works.”

Spray drying is a technological process used to dry materials from free-flowing fluids into powders of various shapes and sizes, and results in the production of powders collected for use in industries like food, dairy, chemical, ceramics, and pharmaceuticals.

When materials are spray dried, heated air vaporizes liquid slurry that has been atomized inside a drying chamber, and any solids suspended in the slurry are then rapidly dried and drawn out of the drying chamber. Next, the powders generated in the dryer chamber must be discharged into a dust collection system. This final step requires a reliable material handling valve to flow smoothly.

Anhydro Inc is a global manufacturer of spray drying equipment, and are known in the spray drying industry for their equipment’s ease of operation, energy-efficient components, and process automation. The Vacu-Valve is an example: it uses no electricity or controls, and starting around $600, is a fraction of the cost of the rotary valve it typically replaces. This valve’s unique duck-bill rubber sleeve utilizes the negative pressure buildup within the dust collection system to maintain a proper airlock seal. As collected material builds up above the valve, the sleeve is forced open to allow product to discharge from the hopper. The valve then re-closes automatically. The Vacu-Valve is available with a variety of sleeve materials to suit various application requirements.

Stewart Gibson, the process engineer in charge of industrial sales at Anhydro, has been recommending the Abanaki Vacu-Valve on ceramic spray drying systems since he joined the company more than three decades ago. When asked why he prefers the Vacu-Valve to a more commonly used rotary valve, his answer was immediately “simplicity…the Vacu-Valve is a simple powder release valve that prevents ingress of air into the system, which is just what we needed.”

Mr. Gibson says there are particular applications the valve is especially well suited to, like those with “dense, free-flowing powders… [and that] the free-flowing nature of materials like ceramics makes this valve suitable for use.” Gibson continues to choose Aerodyne’s Vacu-Valve for Anhydro Inc. because of the “reduced maintenance and high reliability” it offers. With no controls or moving parts like the rotary valve, he said, it just works.