Fremgangsmåde til fjernelse af sod fra en vandig sodsuspension.

摘要

1394124 Removing soot from water SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ NV 4 April 1972 [6 April 1971] 15383/72 Headings C1A and C1C A process for removing soot from an aqueous suspension comprises, in a mixing zone, mixing the suspension with a water-immiscible auxiliary liquid under turbulent conditions to form a dispersion of agglomerates of soot and auxiliary liquid in water, and, in a separating zone, bring- ing the aqueous dispersion of agglomerates into contact with an unstirred phase of waterimmiscible auxiliary liquid whereby the agglomerates pass into this phase, discharging a substantially agglomerate-free aqueous phase and mechanically removing the agglomerates from the auxiliary liquid phase. The auxiliary liquid used in the separating zone may be the same or different to that used in the mixing zone. The auxiliary liquid may be one or more of toluene, benzene, gasoline and naphtha. The aqueous suspension may be produced by washing synthesis gas with water. The temperature and pressure in the zones may be respectively 40- 160‹ C. and 1-15 kg./cm.2. The discharged aqueous phase may have ash removed therefrom by flotation and then may be used to wash soot-containing gas. The separated agglomerates may be dried on inclined heated plates and dispersed in a heavy oil (e.g. fuel oil) or dried to a powder using inclined heated plates and/or a fluidized bed using superheated steam. In Fig. 2 the soot suspension from line 8 and auxiliary liquid from line 9 is mixed by rotating stirrers 6 in zone 1 and the resultant agglomerate dispersion is passed to zone 2 where the agglomerates pass into auxiliary liquid phase 12 supplied with liquid from line 13, and the separated water is discharged through line 10. The agglomerates are removed from phase 12 by Archimedean screw 15 and passed to evaporator 39 supplied with hot heavy oil from lines 42 and 46. From evaporator 39 evaporated auxiliary liquid is passed through line 41 to tray-type stripper 48, a portion of agglomerates and oil is recirculated to line 42 and a portion of agglomerates and oil is passed to stripper 48 supplied with steam from line 52. A suspension of soot in oil is discharged through line 51 and steam and auxiliary liquid vapour are discharged through line 49 to condenser 53 from which water is discharged through line 54 and auxiliary liquid is discharged through line 55 for return to stripper 48 by line 56 and the zones 1 and 2 by line 36.