METHOD AND SYSTEM FOR TREATING SLUDGE

摘要

The present invention provides a method and system for treating sludge, which can be used as improved facility useful to conventional sludge treatment facility where a dehydrating process is followed by a drying process and a discharging process and has an effect of inhibiting an increase in fuel costs. The method for treating sludge according to the present invention comprise: a dehydrating process for dehydrating raw sludge; a methane fermentation process for hydrating the dehydrated sludge to obtain slurry-phase sludge and then ferment the slurry-phase sludge with methane to obtain digested sludge; a separating process for separating the digested sludge into first digested sludge and second digested sludge; a decompressed degassing process for degassing the first digested sludge under reduced pressure; a vacuum creating process for spouting high-temperature vapor at a high speed to create vacuum and returning the concentrated digested sludge along with the high-temperature vapor to the methane fermentation process; and a dehydrating and separating process for separating the second digested sludge into the digested dehydrated sludge and separated sludge liquid. In addition, the method further comprises: a decompressed degassing process for degassing the digested sludge created from methane fermentation; a separating process for spouting high-temperature vapor at a high speed to create vacuum, thereby obtaining a mixed-phase fluid, and then separating the mixed-phase fluid; and a returning process for returning the separated first mixed-phase fluid to the methane fermentation and returning the second mixed-phase fluid to the dehydrating and separating process.