Sewage sludge milling machine comprises many milling blades arranged along their axes of rotation on a rotating shaft extended in an operating state across a drying bed for sewage sludge drying

摘要

Sewage sludge milling machine (50) comprises many milling blades (52), which are arranged along their axes of rotation on a rotating shaft (54), which is extended in an operating state across a drying bed (12) for the sewage sludge drying, and is translationally movable in a longitudinal direction of the drying bed, and lowerably arranged to the drying bed in such a manner that a granulation of the sewage sludge takes place during a superimposed translation and rotation of the blades, and thus the drying time is shortened by increasing the surface area. Independent claims are also included for: (1) low temperature drying of the sewage sludge with warm drying air, comprising introducing wet sewage sludge on the drying bed, pre-drying the sludge in a pre-drying phase, and subsequently post-drying the sludge in a post-drying phase, where warm drying air of the pre-drying phase is at least partially exhaust air from the post-drying phase, and is supplied by a fan into the sewage sludge of the pre-drying phase; and (2) a low-temperature sewage sludge drying system for performing the above method, comprising a first drying zone for pre-drying of the wet sewage sludge input on the drying bed in the pre-drying phase, and a second drying zone for post-drying of the pre-dried sewage sludge on the drying bed in the post-drying phase, where at least one fan is provided for direct supply of exhaust air from the second drying zone into the first drying zone.