{"id":{"repo_id":"washington","oai_identifier":"oai:digital.lib.washington.edu:1773/23555"},"canonical_url":"https://search.dev.ndltd.org/etd/washington/oai:digital.lib.washington.edu:1773/23555","repository":{"repo_id":"washington","name":"University of Washington","base_url":"https://digital.lib.washington.edu/server/oai/request"},"display":{"title":"Gasification of in-Forest Biomass Residues","abstract":"Described is a laboratory-scale continuous-feed supercritical water gasification (SCWG) system. The system is operated using real-world Ponderosa Pine sawmill residues at high biomass loadings, short mean residence times (2-5 sec), and 27.7 MPa pressures. Each run with the SCWG system typically processed several 100 g of biomass/water slurry mixture. We evaluated the effect of operating temperatures (from 700K to 900K) and biomass feedstock loadings (5% to 15% by weight in water) on solids conversion and gaseous product composition. Biomass-to-gasified product conversion efficiencies ranged from 89% to 99%, by mass. Gaseous products were primarily composed of CO2, H2, CH4, and CO, generally in that order of prevalence. The highest hydrogen yield, 43% mole percent, was achieved at 900k with a 5% biomass loading. In general, low biomass loadings corresponded to higher H2:CO2 ratios, but never did we observe stoichiometries that could be explained purely by steam reforming or steam reforming plus water gas shift chemistries. Methanation & Hydrogenation chemistry also occurred, but the mole fraction of CH4 never exceeded 10%. We hypothesize that the real-world biomass samples used here intrinsically include gas-bubbles in the slurry, enabling partial or complete oxidation to occur along with the more conventional SCWG chemistries. As a result, the observed syngas composition was shown to depend more on biomass loading than on processing temperature. In-situ Raman testing was also evaluated as a possible means of monitoring SCWG real time. Biomass (lignin, cellulose, and hemicellulose) were all detected along with variations in concentration. Additionally effluent composition was verified to not contain intermediary compounds.","abstract_html":"Described is a laboratory-scale continuous-feed supercritical water gasification (SCWG) system. The system is operated using real-world Ponderosa Pine sawmill residues at high biomass loadings, short mean residence times (2-5 sec), and 27.7 MPa pressures. Each run with the SCWG system typically processed several 100 g of biomass/water slurry mixture. We evaluated the effect of operating temperatures (from 700K to 900K) and biomass feedstock loadings (5% to 15% by weight in water) on solids conversion and gaseous product composition. Biomass-to-gasified product conversion efficiencies ranged from 89% to 99%, by mass. Gaseous products were primarily composed of CO2, H2, CH4, and CO, generally in that order of prevalence. The highest hydrogen yield, 43% mole percent, was achieved at 900k with a 5% biomass loading. In general, low biomass loadings corresponded to higher H2:CO2 ratios, but never did we observe stoichiometries that could be explained purely by steam reforming or steam reforming plus water gas shift chemistries. Methanation & Hydrogenation chemistry also occurred, but the mole fraction of CH4 never exceeded 10%. We hypothesize that the real-world biomass samples used here intrinsically include gas-bubbles in the slurry, enabling partial or complete oxidation to occur along with the more conventional SCWG chemistries. As a result, the observed syngas composition was shown to depend more on biomass loading than on processing temperature. In-situ Raman testing was also evaluated as a possible means of monitoring SCWG real time. Biomass (lignin, cellulose, and hemicellulose) were all detected along with variations in concentration. Additionally effluent composition was verified to not contain intermediary compounds.","abstract_has_math":false,"creators":["Faires, Kenneth B."],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Schwartz, Daniel T"],"committee_chairs":[],"committee_members":[],"year":2013,"date_issued":"2013-07-25","date_published":"2013-07-25","updated_at":"2026-07-24T05:58:16Z","subjects":["biofuel; biomass; gasification; supercritical"],"languages":["en_US"],"rights":["Copyright is held by the individual authors."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/1773/23555","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Schwartz, Daniel T"]},{"key":"dc:creator","label":"Author","values":["Faires, Kenneth B."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2013-07-25T17:53:30Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2013-07-25T17:53:30Z"]},{"key":"dc:date.issued","label":"Date","values":["2013-07-25"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["biofuel; biomass; gasification; supercritical"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en_US"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright is held by the individual authors."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["Faires_washington_0250E_11862.pdf"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/1773/23555"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Thesis (Ph.D.)--University of Washington, 2013"]},{"key":"dc:description.abstract","label":"Abstract","values":["Described is a laboratory-scale continuous-feed supercritical water gasification (SCWG) system. The system is operated using real-world Ponderosa Pine sawmill residues at high biomass loadings, short mean residence times (2-5 sec), and 27.7 MPa pressures. Each run with the SCWG system typically processed several 100 g of biomass/water slurry mixture. We evaluated the effect of operating temperatures (from 700K to 900K) and biomass feedstock loadings (5% to 15% by weight in water) on solids conversion and gaseous product composition. Biomass-to-gasified product conversion efficiencies ranged from 89% to 99%, by mass. Gaseous products were primarily composed of CO2, H2, CH4, and CO, generally in that order of prevalence. The highest hydrogen yield, 43% mole percent, was achieved at 900k with a 5% biomass loading. In general, low biomass loadings corresponded to higher H2:CO2 ratios, but never did we observe stoichiometries that could be explained purely by steam reforming or steam reforming plus water gas shift chemistries. Methanation & Hydrogenation chemistry also occurred, but the mole fraction of CH4 never exceeded 10%. We hypothesize that the real-world biomass samples used here intrinsically include gas-bubbles in the slurry, enabling partial or complete oxidation to occur along with the more conventional SCWG chemistries. As a result, the observed syngas composition was shown to depend more on biomass loading than on processing temperature. In-situ Raman testing was also evaluated as a possible means of monitoring SCWG real time. Biomass (lignin, cellulose, and hemicellulose) were all detected along with variations in concentration. Additionally effluent composition was verified to not contain intermediary compounds."]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Gasification of in-Forest Biomass Residues"]}]}],"canonical_facts":{"dc:contributor.advisor":["Schwartz, Daniel T"],"dc:creator":["Faires, Kenneth B."],"dc:date.accessioned":["2013-07-25T17:53:30Z"],"dc:date.available":["2013-07-25T17:53:30Z"],"dc:date.issued":["2013-07-25"],"dc:description":["Thesis (Ph.D.)--University of Washington, 2013"],"dc:description.abstract":["Described is a laboratory-scale continuous-feed supercritical water gasification (SCWG) system. The system is operated using real-world Ponderosa Pine sawmill residues at high biomass loadings, short mean residence times (2-5 sec), and 27.7 MPa pressures. Each run with the SCWG system typically processed several 100 g of biomass/water slurry mixture. We evaluated the effect of operating temperatures (from 700K to 900K) and biomass feedstock loadings (5% to 15% by weight in water) on solids conversion and gaseous product composition. Biomass-to-gasified product conversion efficiencies ranged from 89% to 99%, by mass. Gaseous products were primarily composed of CO2, H2, CH4, and CO, generally in that order of prevalence. The highest hydrogen yield, 43% mole percent, was achieved at 900k with a 5% biomass loading. In general, low biomass loadings corresponded to higher H2:CO2 ratios, but never did we observe stoichiometries that could be explained purely by steam reforming or steam reforming plus water gas shift chemistries. Methanation & Hydrogenation chemistry also occurred, but the mole fraction of CH4 never exceeded 10%. We hypothesize that the real-world biomass samples used here intrinsically include gas-bubbles in the slurry, enabling partial or complete oxidation to occur along with the more conventional SCWG chemistries. As a result, the observed syngas composition was shown to depend more on biomass loading than on processing temperature. In-situ Raman testing was also evaluated as a possible means of monitoring SCWG real time. Biomass (lignin, cellulose, and hemicellulose) were all detected along with variations in concentration. Additionally effluent composition was verified to not contain intermediary compounds."],"dc:format.mimetype":["application/pdf"],"dc:identifier.other":["Faires_washington_0250E_11862.pdf"],"dc:identifier.uri":["http://hdl.handle.net/1773/23555"],"dc:language.iso":["en_US"],"dc:rights":["Copyright is held by the individual authors."],"dc:subject":["biofuel; biomass; gasification; supercritical"],"dc:title":["Gasification of in-Forest Biomass Residues"],"dc:type":["Thesis"]},"updated_at":"2026-07-24T05:58:16Z"}