Process for modifying fibre webs composed of oxidic materials for use in dust collection from gases

摘要

For the dust collection from gases there is proposed a process for chemically modifying fibre webs composed of oxidic materials. An acid and thermal treatment and also an aftertreatment with liquids which contain Al, B and/or Si compounds make it possible to modify individual fibres and the pore texture of the fibre webs in such a way that depth filtration can be suppressed in favour of surface filtration. This makes it possible to very substantially prevent an irreversible pressure loss increase during the filtration due to blinding of the filter web.