METHOD AND DEVICE FOR DRYING PASTE MATERIALS, IN PARTICULAR SILT DEPOSITS OF WASTE WATER TREATMENT STATIONS, WITH HEAT ENERGY PRODUCTION

摘要

1. A method of drying pasty materials, in particular silty sediments of wastewater treatment plants, comprising two stages of drying, in which they carry out: - the first stage (1) of drying an indirect type, fed by a heat-transfer fluid, and this first stage provides an output ( 1a, 1b) of pre-dried silt sediments and water vapor; - step (6) of forming silt sediments at the outlet of the aforementioned first stage; - the second stage (7) of drying already pre-dried silt deposits, which are heated by means of a heating gas, in particular hot air, and this second stage of drying gives finally dried mud deposits at the outlet (7b), characterized in that: - pre-dried mud deposits coming from the first stage (1) dried, introduced into the extruder (6) for mud deposits, having the ability to form cords from these mud deposits or similar forms that fall into the second drying device (7); - dried mud deposits, according to step from the second stage of drying, is subjected to mechanical action (19) in order to give them a granular shape, and at least part of the granules thus obtained is subjected to burning (23) in order to generate thermal energy; and - at least a portion of this thermal energy is used to heat the heat-carrying fluid in the first drying stage. 2. The method according to claim 1, characterized in that the water vapor leaving the first drying stage (1b) is sent to a condenser (12) so that