High-velocity vacuum drying of forest industry sludge materials

Novel, economically and environmentally viable drying methods are required for the use of forest industry sludge materials as potential future resources. High-velocity vacuum drying is a technology capable of utilizing the low-temperature secondary energies of industrial environments, hence offering potentially significant improvements in the energy efficiency of drying operations.

However, a more comprehensive understanding of material effects and optimization opportunities is required. Laboratory scale convective drying experiments will identify boundary conditions for forest industry sludge materials to support the construction of a laboratory set-up for simulating high-velocity vacuum drying in laboratory scale. In addition, the project incorporates novel sludge characterization methods to characterize processing effects of high-velocity vacuum drying in pilot scale: X-ray fluorescence spectroscopy for identification of inorganic components and near infrared spectroscopy and dynamic vapour sorption for determination of moisture distribution and sorption mechanisms.

The results of this project are used to determine the possibilities for a breakthrough technology and serves as a platform for future development of the high-velocity vacuum drying processes. For the industry, this would enable significant savings in the cost-efficiency of current production and generate novel business models for the sustainable use and management of natural resources.