Depth filters are used in air-conditioning, cleanroom technology and exhaust gas treatment. Particles are separated inside a porous structure where they form particulate structures. High flow velocities are needed to detach particles adhering to the filter media, for example velocities greater than 1 m/s are needed for detaching particles of 10 µm in diameter. Velocities in filtration processes are lower because particle bounce occurs at [endif]--> 1 m/s, reducing separation efficiency. For this reason, detachment of separated particles does not happen in most filtration processes. New findings show that reactive components in deposited particle structures can cause deformation and detachment even at low flow velocities. Understanding of these phenomena is necessary to improve soot particle filtration in fibrous filters. In the scope of this project first experimental results regarding deformation and detachment of soot agglomerates on/from a single steel fiber exposed to hot air flow are presented...