Low absolute pressures are used in the vacuum drying of temperature-sensitive bulk materials—such as pharmaceutical formulations, powders for the chemical and food industries, or components for battery cell manufacturing. During this process, fine particles can be carried away by the rising vapor. To protect downstream plant components, these particles are captured. In industrial practice, surface filters are predominantly used for this purpose. A key advantage of surface filters is that the bulk materials—which are often high-value—can be recovered through filter regeneration.

To date, the design and operation of such filters have been based primarily on insights gained from normal-pressure processes. In particular, it is unclear how the altered pressure conditions during vacuum drying affect the regeneration behavior and, consequently, the operation of the filters.

The target of this research project is to conduct a fundamental investigation of the regeneration behavior of surface filters at low absolute pressures. Recommendations for the design and operation of regeneration systems in low-pressure filtration will be derived from the results.