Valorization of animal and human wastes through hydrothermal liquefaction for biocrude production and simultaneous recovery of nutrients

Co-liquefaction of sewage sludge with wheat straw in supercritical water – potential for integrating hydrothermal liquefaction with wastewater treatment plants

“…Lipids in fact usually show higher conversion efficiency compared to proteins, which in turn show higher conversion efficiency with respect to cellulosics. 4,19 Moreover, the fixed carbon in straw (21.9%) is higher than that in SS (7.9%) and the fixed carbon and biocrude yield were previously found to be inversely correlated. 4 Higher biocrude yields could therefore be expected from feed where SS prevails on straw.…”

“…The organic fraction is thermochemically converted into an energy-dense crude oil, which can be upgraded to advanced biofuels or chemicals, while the inorganic fraction is concentrated in a solid phase, which can be used as a source of nutrients in agriculture. 4 The relatively high temperatures (350–400 °C) used in HTL have also shown to be effective to a great extent in both plastic reduction 5–7 and removal of pathogenic compounds. 8,9 Using SS as a feedstock in HTL allows for a constant supply of raw material, since wastewater is continuously conveyed towards WWTPs through the sewerage system.…”

Hydrochar derived from municipal sludge through hydrothermal processing: A critical review on its formation, characterization, and valorization

“…-131 --a db = dry basis; TS = total solids of sludge feedstock; VM = volatile matter; FC = fixed carbon; HHV = higher heating value; references (Acelas et al, 2014;Afif et al, 2011;Ahn et al, 2020;Alatalo et al, 2013;Ali Shah et al, 2021;Amrullah and Matsumura, 2018;Anastasakis et al, 2018;Aragón-Briceño et al, 2017Becker et al, 2019;Berge et al, 2011;Bhatt et al, 2018;Biller et al, 2018;Breulmann et al, 2017;Brookman et al, 2018;Catallo and Comeaux, 2008;Chang et al, 2021;D. Chen et al, 2020;Chen et al, 2019Chen et al, , 2013bChen et al, , 2013aChu et al, 2020;Conti et al, 2020;Couto et al, 2018;  Results showed that WHSV between 1.5 and 3.1 hr -1 had no noticeable effect on co-HTG;  Co-HTG of MS with corn starch had slightly more H 2 and less CH 4 in gas composition than HTG of corn starch only;  Co-HTG resulted in less TOC yield than HTG of corn starch only. (Xu and Antal, 1998) a DS = digested sludge; FS = fecal sludge; MS = municipal sludge; PS = primary sludge; WAS = waste activated sludge; daf = dry ash free basis; ID = inner diameter; HHV = higher heating value; HTC = hydrothermal carbonization; HTL = hydrothermal liquefaction; WHSV = weight hourly space velocity; HTG = hydrothermal gasification; TOC = total organic carbon.…”

Bio-Crude Production through Recycling of Pretreated Aqueous Phase via Activated Carbon

“…The sulfur was distributed in all phases as 41-49% in the bio-crude; this is because of the cleavage of sulfur atoms from the cyclic organic compounds in the presence of subcritical water. Earlier, Conti et al utilized four feedstocks including SS, and reported 30-60% of the sulfur in the bio-crude phase [52]. An interesting observation was that the distribution of the phosphorus was not impacted via the recycling of the treated aqueous phase.…”