{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/105252"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/105252","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Characterizing the mechanism and rate of calcium phosphate precipitation in aerobic granular sludge","abstract":"With increasingly stringent standards for wastewater treatment plant effluent, the demand for technologies that are able to increase phosphorus removal while also recovering a valuable and marketable fertilizer product is growing. Aerobic granular sludge (AGS) is a promising technology that has demonstrated the ability to increase phosphorus removal while enhancing recovery through the precipitation of calcium phosphate minerals within the granule1–3. A rigorous understanding of precipitation mechanism and rate has been limited by simultaneous biological uptake and release of phosphate and cations. As a result, more work is needed to better understand how to control and enhance mineral precipitation within the polymeric matrix of the granule as well as how the pre-existing mineral phases within the granule influence recovery. To address this issue we performed precipitation experiments using AGS and solutions supersaturated with respect to hydroxyapatite and CaHPO4. We monitored the solution characteristics (pH, and [P]) in order to quantify the impact of calcium pre-enrichment on the extent and rate of phosphate removal with aerobic granular sludge. Our results showed that the use of calcium enriched granules significantly enhances the extent and rate of phosphorus removal. The final phosphorus concentration decreased from 1.64 mM of P to 1.06 mM of P when comparing calcium enriched granules to the abiotic control. The rate also increased from 1.9 to 11.2 day-1 with the presence of calcium enriched granules. Additionally, a lack of fines production indicated that precipitation was promoted within the granule EPS matrix. Results have also indicated that calcium pre-enrichment increases the transition from amorphous calcium phosphate to more stable forms. XRD analysis resulted in a solids spectra that contained peaks characteristic of hydroxyapatite, suggesting that more crystalline forms of calcium phosphate were deposited within the granules over time. SEM imaging showed an increase in phosphorus and calcium within the granules. Overall, this work identifies conditions under which aerobic granules enhance mineral phosphate precipitation and suggests that calcium treated granular sludge can be used to recover phosphorus as a stable calcium phosphate mineral. Future work will identify the solubilities of the minerals recovered via this process as well as their value as a phosphorous product for agriculture.","abstract_html":"With increasingly stringent standards for wastewater treatment plant effluent, the demand for technologies that are able to increase phosphorus removal while also recovering a valuable and marketable fertilizer product is growing. Aerobic granular sludge (AGS) is a promising technology that has demonstrated the ability to increase phosphorus removal while enhancing recovery through the precipitation of calcium phosphate minerals within the granule1–3. A rigorous understanding of precipitation mechanism and rate has been limited by simultaneous biological uptake and release of phosphate and cations. As a result, more work is needed to better understand how to control and enhance mineral precipitation within the polymeric matrix of the granule as well as how the pre-existing mineral phases within the granule influence recovery. To address this issue we performed precipitation experiments using AGS and solutions supersaturated with respect to hydroxyapatite and CaHPO4. We monitored the solution characteristics (pH, and [P]) in order to quantify the impact of calcium pre-enrichment on the extent and rate of phosphate removal with aerobic granular sludge. Our results showed that the use of calcium enriched granules significantly enhances the extent and rate of phosphorus removal. The final phosphorus concentration decreased from 1.64 mM of P to 1.06 mM of P when comparing calcium enriched granules to the abiotic control. The rate also increased from 1.9 to 11.2 day-1 with the presence of calcium enriched granules. Additionally, a lack of fines production indicated that precipitation was promoted within the granule EPS matrix. Results have also indicated that calcium pre-enrichment increases the transition from amorphous calcium phosphate to more stable forms. XRD analysis resulted in a solids spectra that contained peaks characteristic of hydroxyapatite, suggesting that more crystalline forms of calcium phosphate were deposited within the granules over time. SEM imaging showed an increase in phosphorus and calcium within the granules. Overall, this work identifies conditions under which aerobic granules enhance mineral phosphate precipitation and suggests that calcium treated granular sludge can be used to recover phosphorus as a stable calcium phosphate mineral. Future work will identify the solubilities of the minerals recovered via this process as well as their value as a phosphorous product for agriculture.","abstract_has_math":false,"creators":["Kitt, Dianna Breanna"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"M.S.","degree_level":"Thesis","degree_discipline":"Environ Engr in Civil Engr","degree_department":null,"school":null,"contributors":["Cusick, Roland D."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2019,"date_issued":"2019-08-23T20:48:24Z","date_published":"2019-08-23T20:48:24Z","updated_at":"2026-07-22T22:24:44Z","subjects":["Aerobic Granular Sludge Calcium Phosphate Phosphorus Recovery"],"languages":["en"],"rights":["Copyright 2019 Dianna Kitt"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2142/105252","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Cusick, Roland D."]},{"key":"dc:creator","label":"Author","values":["Kitt, Dianna Breanna"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2019-08-23T20:48:24Z","2021-08-24T09:15:28Z","2019-04-25","2019-05"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Environ Engr in Civil Engr"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M.S."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Aerobic Granular Sludge Calcium Phosphate Phosphorus Recovery"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2019 Dianna Kitt"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/105252"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["With increasingly stringent standards for wastewater treatment plant effluent, the demand for technologies that are able to increase phosphorus removal while also recovering a valuable and marketable fertilizer product is growing. Aerobic granular sludge (AGS) is a promising technology that has demonstrated the ability to increase phosphorus removal while enhancing recovery through the precipitation of calcium phosphate minerals within the granule1–3. A rigorous understanding of precipitation mechanism and rate has been limited by simultaneous biological uptake and release of phosphate and cations. As a result, more work is needed to better understand how to control and enhance mineral precipitation within the polymeric matrix of the granule as well as how the pre-existing mineral phases within the granule influence recovery. To address this issue we performed precipitation experiments using AGS and solutions supersaturated with respect to hydroxyapatite and CaHPO4. We monitored the solution characteristics (pH, and [P]) in order to quantify the impact of calcium pre-enrichment on the extent and rate of phosphate removal with aerobic granular sludge. Our results showed that the use of calcium enriched granules significantly enhances the extent and rate of phosphorus removal. The final phosphorus concentration decreased from 1.64 mM of P to 1.06 mM of P when comparing calcium enriched granules to the abiotic control. The rate also increased from 1.9 to 11.2 day-1 with the presence of calcium enriched granules. Additionally, a lack of fines production indicated that precipitation was promoted within the granule EPS matrix. Results have also indicated that calcium pre-enrichment increases the transition from amorphous calcium phosphate to more stable forms. XRD analysis resulted in a solids spectra that contained peaks characteristic of hydroxyapatite, suggesting that more crystalline forms of calcium phosphate were deposited within the granules over time. SEM imaging showed an increase in phosphorus and calcium within the granules. Overall, this work identifies conditions under which aerobic granules enhance mineral phosphate precipitation and suggests that calcium treated granular sludge can be used to recover phosphorus as a stable calcium phosphate mineral. Future work will identify the solubilities of the minerals recovered via this process as well as their value as a phosphorous product for agriculture.","Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2021-05-01","The student, Dianna Kitt, accepted the attached license on 2019-04-23 at 20:34.","The student, Dianna Kitt, submitted this Thesis for approval on 2019-04-23 at 20:48.","This Thesis was approved for publication on 2019-04-25 at 14:13.","DSpace SAF Submission Ingestion Package generated from Vireo submission #13854 on 2019-08-22 at 16:23:41","Made available in DSpace on 2019-08-23T20:48:24Z (GMT). No. of bitstreams: 2 KITT-THESIS-2019.pdf: 1521327 bytes, checksum: 6babd251aa09677de69632b6a761d6c3 (MD5) LICENSE.txt: 4208 bytes, checksum: 954159e9d1dd5180e603048598b8d9b1 (MD5) Previous issue date: 2019-04-25","Embargo set by: Seth Robbins for item 112374 Lift date: 2021-08-23T20:48:32Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system","Limited Restriction Lifted for Item 112374 on 2021-08-24T09:15:28Z."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Characterizing the mechanism and rate of calcium phosphate precipitation in aerobic granular sludge"]}]}],"canonical_facts":{"dc:contributor":["Cusick, Roland D."],"dc:creator":["Kitt, Dianna Breanna"],"dc:date":["2019-08-23T20:48:24Z","2021-08-24T09:15:28Z","2019-04-25","2019-05"],"dc:description":["With increasingly stringent standards for wastewater treatment plant effluent, the demand for technologies that are able to increase phosphorus removal while also recovering a valuable and marketable fertilizer product is growing. Aerobic granular sludge (AGS) is a promising technology that has demonstrated the ability to increase phosphorus removal while enhancing recovery through the precipitation of calcium phosphate minerals within the granule1–3. A rigorous understanding of precipitation mechanism and rate has been limited by simultaneous biological uptake and release of phosphate and cations. As a result, more work is needed to better understand how to control and enhance mineral precipitation within the polymeric matrix of the granule as well as how the pre-existing mineral phases within the granule influence recovery. To address this issue we performed precipitation experiments using AGS and solutions supersaturated with respect to hydroxyapatite and CaHPO4. We monitored the solution characteristics (pH, and [P]) in order to quantify the impact of calcium pre-enrichment on the extent and rate of phosphate removal with aerobic granular sludge. Our results showed that the use of calcium enriched granules significantly enhances the extent and rate of phosphorus removal. The final phosphorus concentration decreased from 1.64 mM of P to 1.06 mM of P when comparing calcium enriched granules to the abiotic control. The rate also increased from 1.9 to 11.2 day-1 with the presence of calcium enriched granules. Additionally, a lack of fines production indicated that precipitation was promoted within the granule EPS matrix. Results have also indicated that calcium pre-enrichment increases the transition from amorphous calcium phosphate to more stable forms. XRD analysis resulted in a solids spectra that contained peaks characteristic of hydroxyapatite, suggesting that more crystalline forms of calcium phosphate were deposited within the granules over time. SEM imaging showed an increase in phosphorus and calcium within the granules. Overall, this work identifies conditions under which aerobic granules enhance mineral phosphate precipitation and suggests that calcium treated granular sludge can be used to recover phosphorus as a stable calcium phosphate mineral. Future work will identify the solubilities of the minerals recovered via this process as well as their value as a phosphorous product for agriculture.","Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2021-05-01","The student, Dianna Kitt, accepted the attached license on 2019-04-23 at 20:34.","The student, Dianna Kitt, submitted this Thesis for approval on 2019-04-23 at 20:48.","This Thesis was approved for publication on 2019-04-25 at 14:13.","DSpace SAF Submission Ingestion Package generated from Vireo submission #13854 on 2019-08-22 at 16:23:41","Made available in DSpace on 2019-08-23T20:48:24Z (GMT). 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