Study of catalytic post-treatment of the vapours from sewage sludge pyrolysis by means of γ-Al 2 O 3

Catalytic post-treatment of the vapors from sewage sludge pyrolysis by means of γ-Al2O3: Effect on the liquid product properties

“…According to previous results [7][8][9][10], a pyrolysis liquid composed by three phases can be obtained. These phases would be: a minority light organic phase (LOP) rich in hydrocarbons (1.7% mass fraction of sewage sludge fed) with an elevated higher heating value (43.1 MJ · kg −1 ), a viscous organic phase (9.0% mass fraction of sewage sludge fed) named heavy organic phase (HOP), rich in fatty acids and triglycerides with a relatively high higher heating value (33.6 MJ · kg −1 ) and an aqueous phase (~23% mass fraction of sewage sludge fed).…”

“…The proximate, elemental and heating value analyses of the sewage sludge can be consulted elsewhere [10].…”

“…Previously to its use as catalyst, the γ-Al 2 O 3 was activated by ex-situ calcination at 600°C during 3 h and kept in a desiccator before its use in the secondary catalytic fixed bed reactor. Further details on its characterization can be found in a previous work [10].…”

“…The postcatalytic treatment was performed using a tubular Fixed Bed Reactor (FixBR). Further details can be checked elsewhere [10].…”

“…In a previous work [10], the effect of the catalytic treatment of the hot sewage sludge pyrolysis vapors over γ-Al 2 O 3 on the yield to the pyrolysis products was studied. It was shown that the aforementioned treatment did not entail a significant drop in the organic phase yields and, what is foremost important, a single and apparently non-viscous organic phase was obtained.…”