{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/105729"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/105729","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Kinetics based characterization of struvite dissolution","abstract":"As phosphorus removal and recovery has become the new standard of wastewater treatment new technologies have quickly been implemented to meet the task. The Ostara Pearl is a crystallizer technology well known in the field of struvite precipitation for plants equipped with enhanced biological phosphorus removal (EBPR). By feeding anaerobically digested EBPR sludge to the Pearl and dosing Mg, struvite precipitation is induced for high rates of P removal. However, one downfall of crystallizers is the generation of poorly characterized fine particulate matter during normal operation, which leave the reactor and disrupt EBPR efficacy. The main objective of this work was to characterize the dissolution of field grown struvite from an Ostara Pearl reactor. Dissolution rate constants between 0.94 and 2.61 mm/min were found for field grown struvite using the shrinking object model – a surface area dependent empirical kinetics-based dissolution model. Enhanced solubility of some field recovered struvite relative to reference struvite was also observed in short-term experiments leading to a need a deeper characterization of those samples. Long-term dissolution experiments, used to characterize the dissolution of any co-precipitants, found little Ca, Fe, and K content in field grown struvite. XRD and FTIR were used to identify any physical and chemical differences in field grown struvite samples which exhibited increased solubility compared to a reference struvite sample. Dittmarite (MgNH4PO4*H2O) and another unknown crystalline solid were found to potentially lead to enhanced solubility. The importance of characterizing plant specific struvite was noted when instances of enhanced solubility were seen in samples which exhibit distinct FTIR bands when comparing surface to internal spectra.","abstract_html":"As phosphorus removal and recovery has become the new standard of wastewater treatment new technologies have quickly been implemented to meet the task. The Ostara Pearl is a crystallizer technology well known in the field of struvite precipitation for plants equipped with enhanced biological phosphorus removal (EBPR). By feeding anaerobically digested EBPR sludge to the Pearl and dosing Mg, struvite precipitation is induced for high rates of P removal. However, one downfall of crystallizers is the generation of poorly characterized fine particulate matter during normal operation, which leave the reactor and disrupt EBPR efficacy. The main objective of this work was to characterize the dissolution of field grown struvite from an Ostara Pearl reactor. Dissolution rate constants between 0.94 and 2.61 mm/min were found for field grown struvite using the shrinking object model – a surface area dependent empirical kinetics-based dissolution model. Enhanced solubility of some field recovered struvite relative to reference struvite was also observed in short-term experiments leading to a need a deeper characterization of those samples. Long-term dissolution experiments, used to characterize the dissolution of any co-precipitants, found little Ca, Fe, and K content in field grown struvite. XRD and FTIR were used to identify any physical and chemical differences in field grown struvite samples which exhibited increased solubility compared to a reference struvite sample. Dittmarite (MgNH4PO4*H2O) and another unknown crystalline solid were found to potentially lead to enhanced solubility. The importance of characterizing plant specific struvite was noted when instances of enhanced solubility were seen in samples which exhibit distinct FTIR bands when comparing surface to internal spectra.","abstract_has_math":false,"creators":["Aguiar, Samuel Enrique"],"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":"2019-11-26T20:35:18Z","date_published":"2019-11-26T20:35:18Z","updated_at":"2026-07-22T22:24:45Z","subjects":["Struvite","dissolution","dissolution rate constant","shrinking object model","Phosphorus recovery","Ostara","Pearl","Nutrient Recovery"],"languages":["en"],"rights":["Copyright 2019 Samuel Aguiar"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2142/105729","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":["Aguiar, Samuel Enrique"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2019-11-26T20:35:18Z","2019-07-19","2019-08"]},{"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":["Struvite","dissolution","dissolution rate constant","shrinking object model","Phosphorus recovery","Ostara","Pearl","Nutrient 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 Samuel Aguiar"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/105729"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["As phosphorus removal and recovery has become the new standard of wastewater treatment new technologies have quickly been implemented to meet the task. The Ostara Pearl is a crystallizer technology well known in the field of struvite precipitation for plants equipped with enhanced biological phosphorus removal (EBPR). By feeding anaerobically digested EBPR sludge to the Pearl and dosing Mg, struvite precipitation is induced for high rates of P removal. However, one downfall of crystallizers is the generation of poorly characterized fine particulate matter during normal operation, which leave the reactor and disrupt EBPR efficacy. The main objective of this work was to characterize the dissolution of field grown struvite from an Ostara Pearl reactor. Dissolution rate constants between 0.94 and 2.61 mm/min were found for field grown struvite using the shrinking object model – a surface area dependent empirical kinetics-based dissolution model. Enhanced solubility of some field recovered struvite relative to reference struvite was also observed in short-term experiments leading to a need a deeper characterization of those samples. Long-term dissolution experiments, used to characterize the dissolution of any co-precipitants, found little Ca, Fe, and K content in field grown struvite. XRD and FTIR were used to identify any physical and chemical differences in field grown struvite samples which exhibited increased solubility compared to a reference struvite sample. Dittmarite (MgNH4PO4*H2O) and another unknown crystalline solid were found to potentially lead to enhanced solubility. The importance of characterizing plant specific struvite was noted when instances of enhanced solubility were seen in samples which exhibit distinct FTIR bands when comparing surface to internal spectra.","Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2019-11-26 without embargo terms","The student, Samuel Aguiar, accepted the attached license on 2019-07-19 at 14:09.","The student, Samuel Aguiar, submitted this Thesis for approval on 2019-07-19 at 14:18.","This Thesis was approved for publication on 2019-07-19 at 14:56.","DSpace SAF Submission Ingestion Package generated from Vireo submission #14396 on 2019-11-26 at 12:54:34","Made available in DSpace on 2019-11-26T20:35:18Z (GMT). No. of bitstreams: 3 AGUIAR-THESIS-2019.pdf: 1658769 bytes, checksum: 555fae3cafe71203eef07fc973839e38 (MD5) S Aguiar Thesis Complete Final.docx: 2811713 bytes, checksum: 761e195a7ac0b866632589c46d0ad08d (MD5) LICENSE.txt: 4210 bytes, checksum: 07bc98b375f66a2d56a50391593a9483 (MD5) Previous issue date: 2019-07-19"]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Kinetics based characterization of struvite dissolution"]}]}],"canonical_facts":{"dc:contributor":["Cusick, Roland D"],"dc:creator":["Aguiar, Samuel Enrique"],"dc:date":["2019-11-26T20:35:18Z","2019-07-19","2019-08"],"dc:description":["As phosphorus removal and recovery has become the new standard of wastewater treatment new technologies have quickly been implemented to meet the task. The Ostara Pearl is a crystallizer technology well known in the field of struvite precipitation for plants equipped with enhanced biological phosphorus removal (EBPR). By feeding anaerobically digested EBPR sludge to the Pearl and dosing Mg, struvite precipitation is induced for high rates of P removal. However, one downfall of crystallizers is the generation of poorly characterized fine particulate matter during normal operation, which leave the reactor and disrupt EBPR efficacy. The main objective of this work was to characterize the dissolution of field grown struvite from an Ostara Pearl reactor. Dissolution rate constants between 0.94 and 2.61 mm/min were found for field grown struvite using the shrinking object model – a surface area dependent empirical kinetics-based dissolution model. Enhanced solubility of some field recovered struvite relative to reference struvite was also observed in short-term experiments leading to a need a deeper characterization of those samples. Long-term dissolution experiments, used to characterize the dissolution of any co-precipitants, found little Ca, Fe, and K content in field grown struvite. XRD and FTIR were used to identify any physical and chemical differences in field grown struvite samples which exhibited increased solubility compared to a reference struvite sample. Dittmarite (MgNH4PO4*H2O) and another unknown crystalline solid were found to potentially lead to enhanced solubility. The importance of characterizing plant specific struvite was noted when instances of enhanced solubility were seen in samples which exhibit distinct FTIR bands when comparing surface to internal spectra.","Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2019-11-26 without embargo terms","The student, Samuel Aguiar, accepted the attached license on 2019-07-19 at 14:09.","The student, Samuel Aguiar, submitted this Thesis for approval on 2019-07-19 at 14:18.","This Thesis was approved for publication on 2019-07-19 at 14:56.","DSpace SAF Submission Ingestion Package generated from Vireo submission #14396 on 2019-11-26 at 12:54:34","Made available in DSpace on 2019-11-26T20:35:18Z (GMT). No. of bitstreams: 3 AGUIAR-THESIS-2019.pdf: 1658769 bytes, checksum: 555fae3cafe71203eef07fc973839e38 (MD5) S Aguiar Thesis Complete Final.docx: 2811713 bytes, checksum: 761e195a7ac0b866632589c46d0ad08d (MD5) LICENSE.txt: 4210 bytes, checksum: 07bc98b375f66a2d56a50391593a9483 (MD5) Previous issue date: 2019-07-19"],"dc:format":["application/pdf"],"dc:identifier":["http://hdl.handle.net/2142/105729"],"dc:language":["en"],"dc:rights":["Copyright 2019 Samuel Aguiar"],"dc:subject":["Struvite","dissolution","dissolution rate constant","shrinking object model","Phosphorus recovery","Ostara","Pearl","Nutrient Recovery"],"dc:title":["Kinetics based characterization of struvite dissolution"],"dc:type":["text"],"thesis:degree_discipline":["Environ Engr in Civil Engr"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["M.S."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:24:45Z"}